Gordon Brown was urged last night to fight back against “bullying tactics” by nations determined to water down British sovereignty in the European Union treaty.

Last-minute changes to the Reform Treaty, which is due to be agreed at the end of the week, will make it harder for Britain to preserve the so-called red lines that the Prime Minister said will defend national control over justice and police systems, critics claimed.

Britain faces new penalties, including a financial price, if it uses its hard-won ability to opt out of EU policies.

The moves will give Mr Brown his first big test on the international stage when EU leaders gather in Lisbon on Thursday.

Mr Brown, who faced renewed calls from the Conservatives yesterday to call a referendum on the treaty, will also be challenged to answer claims that Britain’s safeguards against the European Court of Justice overriding British law will be eroded over time.

“This is a bullying tactic and it is one that is entirely unacceptable,” Michael Connarty, the Labour MP who chairs the Commons EU Scrutiny Committee, said yesterday. “The least that the Prime Minister should do is say, ‘I am not prepared to accept this’.”

The pressure on Britain not to use its opt-outs was raised yesterday by José Manuel Barroso, the European Commission President, when he gave warning that, unless Britain co-operated fully with EU measures, it would hinder the fight against terrorism.

The treaty, which will change the way the EU is run to reflect its enlargement, has been drawn up at high speed to replace the rejected EU constitution in time for elections to the European Parliament in 2009. It will end national vetoes over 50 policy areas.

In exchange for giving up the right to veto new EU measures on criminal justice, Britain has won the ability to opt in on a case-by-case basis. EU nations angry at this arrangement, including Italy and Spain, have inserted a clause giving them the power to exclude Britain from entire policy areas if Britain opts out of future changes.

If the EU wanted to create a common DNA database, other EU countries could go ahead while excluding Britain. Were Britain allowed to keep its independent database, the British taxpayer would have to pay any costs incurred by other countries in creating systems to accommodate it — a potentially huge financial penalty.

A government spokesman said that the treaty was simply spelling out an inevitable result of Britain using its opt-outs in some cases. In other cases, he was confident that EU nations would rather keep Britain involved than exclude it entirely. “This is the logical consequence of getting our opt-ins and opt-outs. If you are going to opt out of one part, it does not necessarily make sense to stay in the other parts. But politically it is not likely to be the case that we get kicked out — it is not a decision that would be taken lightly.”

Mr Connarty said: “The redraft of the treaty contains protocols and declarations that were not there before which are much tougher for the UK and threaten the red lines very quickly. It means they will be rubbed out five years from now.”

David Miliband, the Foreign Secretary, today presents the case for Britain’s opt-outs at a meeting of foreign ministers in Luxembourg. In line with the breakneck pace of the talks, the agenda gives 45 minutes for the treaty.

On the agenda
The EU reform treaty includes:

Provision for an EU foreign minister
Permanent President of the European Council
Slimmed-down European Commission
New voting weights for countries
50 national vetoes scrapped
Charter of Fundamental Rights
European Public Prosecutor
“Constitutional concept” abandoned
British opt-outs on justice and home affairs

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