Constitutional practicability of referendum on EU Constitution

Yes. Binding referendum provided if constitutional amendment effected or ordered by presidential plebiscite.

Approval of transfer of sovereignty without effect of constitutional amendment

Majority of both chambers, Art. 53, 46 ConstFrance.

Approval of transfer of sovereignty with effect of constitutional amendment

Previous constitutional amendment required, Art. 54 ConstFrance. Limit for transfer is the integracy of state and the republican form of government, Art. 89 IV ConstFrance.

Approval of constitutional amendment

Majority from both chambers and a referendum on constitutional amendment, Art. 89 ConstFrance. Referendum is not called if both chambers foregathered by proposal of the president as the Congress approves constitutional amendment with majority of 3/5 of the votes, Art. 89 III ConstFrance.

Other constitutional regulations about referendums

By proposal of the government or a joint proposal of both chambers the president can call a referendum on any law that substitutes the approval of the chambers. This presidential plebiscite can only be called for approval of international treaties if constitutional amendment is not effected, Art. 11 ConstFrance.