Text of the Constitution (in English)
1. Provisions concerning the European Union
Art. 62 The President of the Republic shall:
(...) l) call a referendum on the accession of the Czech Republic to the European Union and announce the results.
Art. 87 (1) The Constitutional Court shall rule on:
(...) l) appeals against a decision of the President of the Republic that a referendum on the accession of the Czech Republic to the European Union shall not be called,
m) whether the execution of a referendum on the accession of the Czech Republic to the European Union is in conformity with the Constitutional law regarding the referendum on the accession of the Czech Republic to the European Union and with the implementing law.
2. Provisions concerning International Treaties
Art.1 (1) The Czech Republic is a sovereign, unitary and democratic, law-abiding State, based on respect for the rights and freedoms of man and citizen.
(2) The Czech Republic shall observe its obligations under international law.
Art. 10 Promulgated international agreements, the ratification of which has been approved by the Parliament and which are binding on the Czech Republic, shall constitute a part of the legal order; should an international agreement make provision contrary to a law, the international agreement shall be applied.
Art. 10a (1) An international agreement may provide for a transfer of certain powers of bodies of the Czech Republic to an international organization or institution.
(2) An approval of the Parliament is required to ratify an international agreement stipulated in Subsection 1 unless a constitutional law requires an approval from a referendum.
Art. 10b (1) The Government shall inform the Parliament regularly and in advance on issues related to obligations arising for the Czech Republic from its membership in an international organization or institution stipulated in Section 10a.
(2) The Chambers of Parliament express their opinions on the decisions of such an international organization or institution in a form provided for by their rules of procedure.
(3) An Act on the principles of conduct and relations between both Chambers and in their external relations, may entrust the exercise of the competence of the Chambers under Subsection 2 to a joint body of the Chambers.
Art. 33 (1) If the Chamber of Deputies is dissolved, the Senate shall adopt legal measures regarding matters which cannot be delayed and which would otherwise require the enactment of a law.
(2) However, the Senate may not adopt legal measures regarding the Constitution, the State Budget, the final state budgetary account, the electoral law and international treaties under Article 10.
Art. 39 4) An approval of a three-fifths majority of all Deputies and of a three-fifths majority of Senators in attendance is required to pass a constitutional Act, as well as to approve the ratification of an international agreement stipulated in Section 10a, Subsection 1.
Art. 43 (2) The Parliament shall decide on the participation of the Czech Republic in defense systems of an international organization of which the Czech Republic is a member.
(3) The Parliament shall give its approval of b) participation in peace operations pursuant to a decision of an international organization of which the Czech Republic is a member, and providing there is an approval of the receiving state,
Article 49 An approval of both Chambers of Parliament is required to ratify international agreements
a) governing rights and duties of persons,
b) of alliance, peace, or other political treaties,
c) which result in the membership of the Czech Republic in an international organization,
d) that are economic of a general nature,
e) on other issues to be governed by the law.
Art. 52 (1) For a law to be valid, it must be promulgated.
(2) The law shall stipulate the way a law or an international agreement is promulgated.
Art. 63 (1) The President of the Republic shall furthermore a) represent the State with respect to other countries, b) negotiate and ratify international treaties; he may delegate the negotiation of international treaties to the Government or, with its consent, to its individual members,
Art. 87 (1) The Constitutional Court shall rule on:
i) measures essential for the implementation of a ruling by an international court, which is binding for the Czech Republic, unless it can be implemented in a different manner,
(2) The Constitutional Court shall also decide on the conformity of international agreements under Section 10a and Section 49 with the constitutional order prior to their ratification. Until a ruling of the Constitutional Court is delivered, an agreement cannot be ratified.
Art. 89 (1) A ruling issued by the Constitutional Court shall be enforceable upon its promulgation in a manner set by law, unless the Constitutional Court rules differently on its enforcement.
(2) Enforceable rulings of the Constitutional Court shall be binding for all agencies and individuals.
(3) A decision of the Constitutional Court whereby, in accordance with Section 87, Subsection 2, unconformity of an international agreement with the constitutional order is pronounced, prevents ratification of the agreement until such unconformity is eliminated.
Art. 95 (1) In his/her decision-making, a judge is bound by the law and international agreements constituting part of the legal order; he/she is entitled to assess the conformity of a different legal regulation with the law or with such international agreement.
3. Provisions concerning constitutional reform
Art. 9 (1) The Constitution may be supplemented or amended only by Constitutional Acts.
Art. 39 (4) An approval of a three-fifths majority of all Deputies and of a three-fifths majority of Senators in attendance is required to pass a constitutional Act, as well as to approve the ratification of an international agreement stipulated in Section 10a, Subsection 1.
4. Provisions concerning referendums
See above for dispositions concerning accession to the European Union
Art.10 (2) An approval of the Parliament is required to ratify an international agreement stipulated in Subsection 1 unless a constitutional law requires an approval from a referendum.