UK Conservative government would 'never' join euro

In keeping with the Tories' traditional intergovernmental approach to Europe, the text says: "We believe Britain's interests are best served by membership of a European Union that is an association of its member states."

It also serves up the same set of guarantees on stopping further federalisation of the EU made last November after it became clear that the Lisbon Treaty - strongly disliked by the Conservatives for removing most of the remaining national vetoes - would come into place.

If they are elected into government on 6 May, the Conservatives will make sure the "shameful" episode of the ratification of the Lisbon Treaty without a referendum "can never happen again."

Any further transfer of powers will be subject to a referendum while a "sovereignty bill" will be introduced to make it clear that "ultimate authority" rests with the UK parliament.

It will not agree to the UK's participation in the setting up of a European public prosecutor's office while use of a clause allowing for amendment of the Lisbon Treaty without going through normal ratification procedures would have to be approved by parliament or, if it concerned a "major" issue, by referendum.

A Conservative government would also negotiate "guarantees" on the Charter of Fundamental Rights (the UK has opted out of the rights charter but the Conservatives have previously said they do not believe the opt-out is watertight), on criminal justice and on social and employment legislation.

In these three areas, the Conservatives want to negotiate with European partners "to return powers that we believe should reside with the UK, not the EU."

"We seek a mandate to negotiate the return of these powers from the EU to the UK."

However, the Conservatives also say they will work to ensure the EU fights global poverty and climate change and boosts global economic growth. The importance of a "strong transatlantic relationship" is also underlined.

Although the general EU ground covered by the manifesto remains the same as statements made by Mr Cameron in November, the manifesto is less detailed.

"We want to restore national control over those parts of social and employment legislation that have proved most damaging to our businesses and public services," the Conservative website says on its Europe policy, referring to the EU's rules on the working time and its application to the country's health system.

Back in the EPP?

In Brussels, meanwhile, there is much interest in UK election with the prospect of a Conservative-led British government leading to some fears that London will pursue a more obstructionist policy when it comes to the EU.

In addition, Mr Cameron is something of an unknown entity in the EU capital, most associated with having withdrawn his Conservative MEPs from the centre-right EPP grouping in the European Parliament - home to Germany and France's ruling parties - in favour of setting up an anti-federalist party with smaller political groups.

The move was widely seen as having marginalised the Tories in Europe, something likely to be highlighted should Mr Cameron be elected into office next month.

The EPP has said it expects Mr Cameron to be "pragmatic" and seek to rejoin the group if he becomes prime minister. However, according to the Antonio Lopez-Isturiz, secretary-general of the party, the party would only accept the Conservatives under strict conditions.

"There will be no negotiations. If the [Tories] come back, it will be under [our] terms," he said, according to the Independent.