UKIP leader Nigel Farage has said he will not stand candidates against eurosceptic Tory and Labour MPs at the next general election.
Mr Farage said the treaty would make fundamental changes
Mr Farage told the BBC he did not wish to split the eurosceptic vote.
"We will always try and put what we see as the national interest above our own party interest," he said.
He hopes to achieve UKIP's best ever showing in the next European elections, on the back of the government's refusal to hold a referendum on the EU Treaty.
Outlining his plans for the next general election, expected in 2009 or 2010, Mr Farage told BBC One's Andrew Marr Show: "We will not stand in that general election against MPs from the Conservative or Labour parties who are prepared to campaign on the same issues that we are."
He said he believed a referendum on the Lisbon Treaty was unlikely - because the Liberal Democrats had said they would not oppose it in Parliament.
But he said there could be no deal with eurosceptic MEPs, because the party list system used in European elections meant they could not target specific candidates.
Mr Farage said the treaty - which replaces the failed EU Constitution - was "so fundamental, that it will allow the European Union if it wants to, to literally legislate in every area of our lives".
He accused the EU of taking the constitution, which was rejected by the French and Dutch at referendums, "maintained all the substance, repackaged and presented it and told us we're just going to have to swallow it".
He also expressed some doubts that Conservative leader David Cameron's pledge not to "let matters rest" if the treaty is ratified by Parliament - should the Conservatives win the next general election.
"That is akin to saying: 'If this goes through, I will give you a referendum on our continued membership of the EU'," said Mr Farage.
"If David Cameron is saying that, I would say 'fantastic, that's great.' But I don't really think that he is."
UKIP, the Conservatives and some Labour MPs say there should be a referendum on the new treaty, because Labour made a manifesto commitment to hold a referendum on the EU Constitution at the last general election.
The government says the treaty is very different to the constitution and a referendum is not required.
The European Union (Amendment) Bill is being debated line-by-line by MPs over the coming weeks.
The treaty was signed by Gordon Brown and all EU leaders in December - but must be ratified by all parliaments before coming into force.
Mr Farage also called for a radical cut in MPs' allowances and the number of MPs, because more laws were being made in Europe.
"We're paying more and more politicians - giving them bigger and bigger allowances - for doing less and less work," he said.