The Lisbon Treaty can come into effect only when all 27 member states have deposited a formal document of ratification with, in this case, the Government of Italy.
While Ireland's rejection of the referendum last week puts the entire process in doubt, here is a look at where the Treaty stands among the 27 member states:
Ratified (date of deposition):
Austria (13 May 2008)
Bulgaria (28 April 2008)
Denmark (29 May 2008)
France (14 February 2008)
Hungary (6 February 2008)
Malta (8 February 2008)
Romania (11 March 2008)
Slovenia (24 April 2008)
Ratified (not yet deposited):
Estonia (Signed by President 19 June 2008)
United Kingdom (Royal assent 19 June 2008)
Approved by parliament:
Finland (awaiting Aland vote)
Germany (President's signature delayed pending court case)
Greece
Latvia
Lithuania
Luxembourg
Poland
Portugal
Slovakia
Defeated by referendum: Ireland (12 June 2008)
Legal Challenges:
Czech Republic - Referred to court by upper house of parliament
No firm date:
Belgium (partially approved)
Cyprus
Italy (new government)
Netherlands (approved by lower house 4 June)
Spain (new government)
Sweden
