A cross-party group of MPs is calling on Gordon Brown to renegotiate urgently the wording of the new European Union treaty because they say it risks relegating national parliaments to mere satellites of Brussels.

The demand came as EU foreign ministers, including David Miliband, the Foreign Secretary, prepared to meet in Brussels today to launch the formal Intergovernmental Conference (IGC) that over the next few months will decide the precise treaty language.

Jim Murphy, the Europe minister, will make a statement on the IGC in the Commons today as Europe returns to centre stage at Westminster.

Tomorrow William Hague, the shadow foreign secretary, will make a major speech demanding a referendum on the new treaty, claiming that it transfers considerable powers from Westminster to Brussels.

The Commons' European scrutiny committee has raised serious concerns over a section in the proposed wording of the treaty that states: "National parliaments shall contribute actively to the good functioning of the Union."

MPs are concerned that the word "shall" creates an obligation for Parliament to put the "good functioning" of the EU above its own interests and independence, and could allow European judges to block future opposition to Brussels from British MPs. The provision goes further than previous European treaties and, it is argued, has a far-reaching constitutional impact on the relationship between Parliament and the EU.

Referring to the wording, Michael Connarty, the Labour chairman of the committee, has warned Mr Murphy that "no one should instruct Parliament what to do". He added during a recent session of the committee: "This is a takeover of the rights of this Parliament."

Conservative and Labour MPs plan to use today's debate to extract a promise from Mr Murphy that the Government will use the talks to secure the removal of the clause.

Mark Francois, the Tories' Europe spokesman, said that unless it was amended the treaty "could end up seriously compromising our Parliament's sovereignty and independence".

"It is no wonder that MPs of all parties are deeply concerned about this," he added.

Unless Mr Brown and his ministers can reopen negotiations on the 16-page mandate agreed by Tony Blair last month, he will find it increasingly difficult to beat off calls for a referendum.

Already more than 11,000 people have signed up to a Daily Telegraph campaign calling for a national vote.

At the start of today's formal IGC negotiations foreign ministers will be entitled to raise any issue they wish. But any attempts to change the mandate will be political dynamite.

British attempts to weaken the language will be opposed by the Netherlands. Inclusion of the text, and the word "shall", was a "red line" issue for Dutch prime minister Jan-Peter Balkenende.

He wanted the strong language, regarded by Dutch MPs as requiring the EU to listen to their parliament, to head off domestic calls for a repeat referendum after the Netherlands rejected the original constitution in June 2005. "This exact language followed tough negotiations. I don't think anyone would to reopen this issue," said a Dutch diplomat.

"Having a strong role for parliaments written into the treaty was an important thing for us."

A British official said: "We need to wait for the IGC. These are the kind of issues we will need to raise."

Mr Francois highlighted the issue as "one of many, many problems in the new treaty, which everyone admits is effectively the EU constitution in all but name".

He added: "It is desirable that the Government gets this changed in the negotiations, and the language in the document is closely examined.

"The short answer is simply to let the British people decide in the referendum they were promised."