Angela Merkel was accused yesterday of planning to smuggle key parts of the failed European constitution into a new slimmed-down treaty after a letter to EU leaders in which she suggested a series of presentational changes was leaked.

The German Chancellor listed 12 discussion points for a new treaty, including a new name for the proposed EU foreign minister, as well as the document itself, to make the idea more palatable to sceptical nations such as the British, Czechs and Dutch.

Tony Blair insisted in interviews yesterday that a new EU treaty would not require the referendum he first promised in 2004 because the revised version would not involve constitutional changes.

However, in her letter, seen by The Times, Mrs Merkel showed that she was determined to make only minimal changes to the EU Constitution rejected by French and Dutch voters in 2005.

She said: “Every effort will have to be made to restrict change to what is absolutely necessary to reach an overall agreement and to ensure ratification by all member states.”

She then posed a dozen key questions, including: “How do you assess the proposal made by some member states to use different terminology without changing the legal substance — for example with regard to the title of the treaty, the denomination of legal acts, and the union’s minister of foreign affairs.”

In the same way, she asks whether to “replace the full text of the Charter of Fundamental Rights by a short cross reference having the same legal value”. As proposed by Mr Blair, the replacement for the Constitution could be presented as a treaty that amends the Nice Treaty of 2001, she said, “with the necessary presentational changes resulting from the return to the classical method of treaty changes”.

Mrs Merkel will use the letter as the basis of one-to-one talks with key EU leaders over the next two weeks, including Mr Blair. She hopes to set out a plan for a new treaty at the EU summit in June.

It would be written by Christmas, leaving a year for the 27 EU nations to ratify it before the next European Parliament elections. Neil O’Brien, director of the eurosceptic Open Europe think-tank, said: “This leak shows that we are going to have the same proposals pushed through under a different name, with a few ‘presentational changes’. It is incredibly cynical but the voters are not stupid and will not be fooled.”

William Hague, the Shadow Foreign Secretary, said: “It is vital that any new treaty that transfers power from Britain to the EU should be subject to a referendum.”

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