Among the first laws enacted by the Supreme Council was the Law on the Name and National Emblem which officially promulgated the country's name as the Republic of Lithuania, and reintroduced the historic emblem depicting a mounted knight Vytis. At 10.44 p.m., March 11, 1990, the Supreme Council of the Republic of Lithuania adopted an Act embodying the expectations and hopes of the nation “On the Re-establishment of the Independence of the Republic of Lithuania” which solemnly proclaimed the end of the period of occupation by a foreign government and the beginning of a new era of statehood.

SUPREME COUNCIL OF THE REPUBLIC OF LITHUANIA ACT On the Re-establishment of the State of Lithuania The Supreme Council of the Republic of Lithuania, expressing the will of the nation, decrees and solemnly proclaims that the execution of the sovereign powers of the State of Lithuania, abolished by foreign forces in 1940, is re-established, and henceforth Lithuania again is an independent state. The Act of Independence of 16 February 1918 of the Council of Lithuania and the Constituent Assembly (Seimas) decree of 15 May 1920 on the re-established democratic State of Lithuania never lost their legal effect and comprise the constitutional foundation of the State of Lithuania. The territory of Lithuania is whole and indivisible, and the constitution of no other state is valid on it. The State of Lithuania stresses its adherence to universally recognised principles of international law, recognises the principle of inviolability of borders as formulated in the Final Act of the Conference on Security and Co-operation in Europe in Helsinki in 1975, and guarantees human, civil and ethnic minorities rights. The Supreme Council of the Republic Lithuania, expressing its sovereign power, by this Act begins to realise the complete sovereignty of the State.

124 delegates vote in favor of the Act, 6 abstained and no votes were cast against the Act. The Act confirmed the continuous and unbroken link of the re-established Lithuanian State with the Act of Independence of February 16, 1918, and the Resolution of a democratic Lithuanian Government, passed by Constituent Assembly (Seimas) on May 15, 1920. With this Act the Council committed itself to carry out the functions of the highest authority, the Lithuanian Parliament, which expressed the will of the absolute majority of population. The Supreme Council terminated the validity of the Constitution of the USSR of October 7, 1977, and the Constitution of the Lithuanian SSR of April 20, 1978, declaring the nominal validity of the Constitution of May 12, 1938, within the territory of Lithuania. The Supreme Council announced that the Constitution of 1938 was in force: this fact signified the continuity of the rights of sovereignty of the Lithuanian State. However, to really regulate the life of the state the principal Provisional Law was passed shortly and the validity of the said Constitution was terminated.

The leadership of the USSR reacted to the re-establishment of the Lithuanian State with extreme antagonism. The Congress of People's Deputies declared the Act of the re-establishment of the Lithuanian State "null and void", and President Gorbachov issued an ultimatum demanding that the sovereignty of the USSR be re-established on the territory of Lithuania and that the country abide by the provisions of the Soviet constitution. When Lithuania rejected the ungrounded and illegal demands of the foreign government, the USSR resorted to a policy of threats, blackmail and intimidation. Soviet military control over Lithuanian state borders was strengthen, foreign citizens' access to the country was limited, and the Soviet military units stationed in Lithuania behaved as they pleased.

Beginning with March 13, 1990, after the March 11^th Act on the Re-establishment of an independent Lithuanian State was promulgated, the USSR started applying political and social sanctions against Lithuania. From April until June 1990, it imposed an economic blockade. Later, in order to break the will of the Lithuanian people, the government of the USSR began an open military aggression. Unarmed Lithuanian citizens, encircling the strategically important objects, including the Parliament buildings, guarded them day and night expecting to avoid aggression. In front of the Parliament buildings barricades were set up bearing different slogans and graffiti reflecting the chief aim of the defenders - to defend the re-established statehood of Lithuania. On January 13, 1991, brutally using force against the unarmed population, Soviet troops stormed the state television and radio buildings in Vilnius: 14 people were killed and about 600 civilians were injured. A wave of indignation rolling throughout the world and the determination of the Lithuanians to defend the Parliament of Lithuania stopped the atrocities of the aggressors.

During the days of barricades the Parliament was called "the heart of Lithuania", from 1990 till 1992, it was a political centre of the Lithuanian State. New legislation, which should decide economic and cultural growth of the Republic of Lithuania, as well as Lithuania's international recognition in the international community of states was related to the work of the Parliament. In other words, the objectives of the Supreme Council were similar to those of the Constituent Assembly (Seimas) of 1920. For this reason the Supreme Council later was given the name of the Reconstituent Seimas.

On account of those aggressive actions, on March 24 the Supreme Council (Reconstituent Seimas) adopted the decision to transfer its powers, in case its rights were restricted, to Independent Envoy of the Republic of Lithuania in Washington and at the Holy See Stasys Lozoraitis. The United States of America were among the few countries which did not only refuse to recognise the occupation of the Republic of Lithuania and its annexation in 1940 but also allowed the Embassy of the Republic of Lithuania to function. On March 22, 1990, the Supreme Council (Reconstituent Seimas) passed the Law on the Government and the first Government of the re-established Lithuanian State was formed (the 22^nd Cabinet of Ministers in the history of the Republic of Lithuania). On 24 March 1990, Kazimira Danutė Prunskiene was appointed Prime Minister of the Republic of Lithuania and during her visits abroad was received by US President G. Bush, Prime Minister of Great Britain M. Thatcher, President of France F. Mitterand, Chancellor of Germany H. Kohl.

Provocative actions of the Soviets lasted, in fact, till August 21, 1991, when the communist putsch in Moscow failed. After the failure of the putsch, Lithuania became fully independent of the USSR. The Soviet Socialist Republic of Moldova was the first from the USSR to recognise the independent Republic of Lithuanian on May 30, 1990, and this was the sign to the authorities in Moscow that the Soviet Empire was breaking up. On February 11, 1991, the Independent Republic of Lithuania was recognised by Iceland. On September 17, 1991, Lithuania joined the United Nations and became a full member of a number of other international organisations. At the 86^th Conference of the Inter-Parliamentary Union held on October 7, Lithuania became an IPU member. On January 24-26, 1992, the Secretariat of a new parliamentary organisation - the Baltic Assembly - was established. On 6 September 1992, the USSR recognised the Independence of Lithuania and on 8 September 1992, a treaty was signed with Russia in Moscow in which it was agreed that Russian troops would be pulled out from the territory of Lithuania by August 31, 1993.

During the said period the main concern of the Parliament was not only to restructure the planned economy that was inherited from the Soviet times by adopting new laws, taking into account complicated and threatening conditions but also to prepare the draft of the Constitution and submit it for the referendum of the Lithuanian citizens. Like members of the Constituent Assembly (Seimas) of 1922, members of the working group of the Supreme Council (Reconstituent Seimas) put efforts to consolidate themselves at the close of the activities of the Supreme Council (Reconstituent Seimas) when Sąjūdis representatives were already divided into several factions. The working group co-ordinated different proposals, and drafted the final version of the Constitution. The Lithuanian Supreme Council (Reconstituent Seimas) completed its historic mission by ratifying on October 25, 1992, a new Constitution, approved in a popular referendum, and by adopting the main fundamental law of the Republic of Lithuania on November 6, 1992.

Before expiration of their term of office, deputies of the Supreme Council (Reconstituent Seimas) established the following Parliamentary Groups: Joint Sąjūdis, Polish, Liberal, Lithuanian Democratic Labour Party, Moderate, Reformed Nationalist, Sąjūdis Centre, Sąjūdis Union and National Progress Groups. During the tenure of the Supreme Council four governments were formed led by Kazimira Danutė Prunskienė, Albertas Šimėnas, Gediminas Vagnorius and Aleksandras Algirdas Abišala. By the end of its term, the Supreme Council (Reconstituent Seimas) had also enacted the Law on Elections to the Seimas of the Republic of Lithuania.