TONY Blair was today stepping up his bid to persuade sceptical voters to back the new European constitution.

The Prime Minister was delivering a crucial statement to MPs on the European Union deal sealed in Brussels on Friday night.

But Labour rebels are plotting to derail his attempt to win the referendum, which could be two years away.

Rebel backbenchers were meeting today to set up a group under the banner Labour Against a Superstate.

And Tory leader Michael Howard challenged Mr Blair to call a referendum before the General Election.

Mr Blair was telling MPs the constitution was a boost for Britain and the EU. His statement was coming after he yesterday said the referendum campaign would be a battle between "reality and myth".

He agreed he faced a tough fight to sell the constitution to a sceptical Britain in a referendum.

But he insisted that voters would be won round once they were told the truth about the deal.

Meanwhile, the leader of the Labour rebels,

Ian Davidson, said today's meeting of his group was aimed at gauging the level of support and planning the way ahead.

He said he expected to have the backing of about 100 Labour MPs. But only 20 to 30 would put their heads above the parapet.