"At the heart of Europe"

In the coming weeks we'll be hearing a lot more about the parties' attitudes to the EU ahead of the European elections in June.

And the Conservatives will be trying to make the Lisbon Treaty a big issue in the campaign.

The shadow Foreign Secretary William Hague told his party's Spring Forum that Gordon Brown had debased the coinage of politics for refusing to hold a referendum on the Treaty. He said this was a betrayal of Labour's manifesto promise of a referendum on the failed constitution.

Although ministers say the treaty does not carry the same weight as the constitution, there are many who argue the Government won't hold a referendum because a largely Euro sceptical electorate will vote no.

Yet when Labour came to power back in 1997 Tony Blair hoped to change Britain's attitude to Europe. So how has Labour's policy on Europe evolved over three terms in government?

Leala Padmanabhan has been investigating. Her report begins with a reminder of Tony Blair's enthusiasm towards Europe.