The chancellor is making the first of a series of trips to key EU capitals, as the government bids to renegotiate the UK’s relationship with the union.
George Osborne is meeting officials in Paris for talks, with visits to more cities planned in the next six months.
A referendum on Britain’s EU membership will be held by the end of 2017.
Mr Osborne’s visit comes as UK universities launch their campaign for a “Yes” vote, saying EU membership has an “overwhelmingly positive impact”.
It also comes amid reports David Cameron is planning to hold the referendum in June next year.
On Sunday night, Mr Osborne had dinner with the French Economy Minister Emmanuel Macron, who has previously said the UK should not be able to cherry-pick aspects of the EU.
‘Prosperity and security’
Mr Osborne is to meet French Finance Minister Michel Sapin and Foreign Minister Laurent Fabius later, during which he is expected to acknowledge the process of reform will not be easy.
But he is expected to argue the vote in the UK is an “opportunity” to bring in changes to make Europe more “competitive and dynamic”.
Mr Cameron embarked on a similar tour following the Conservatives’ victory in the May general election.
In Paris, the chancellor is expected to say: “We have been returned to office with a very clear mandate to improve Britain’s relationship with the rest of the EU and to reform the EU.
“I want to see a new settlement for Europe: one that makes it a more competitive and dynamic continent to ensure it delivers prosperity and security for all of the people within it, not just for those in Britain.”
He will add: “This government wants the UK to play a leading role within a reformed EU.”
What does renegotiation mean?
The prime minister has not set out in full detail what he wants but his key demands include:
- An opt-out on the core EU aim of “ever closer union”
- The sovereignty of national parliaments to be boosted, so groups of them can block proposed EU legislation
- Safeguard the City of London and other financial centres outside the eurozone
- Curb EU immigration by cutting benefits
- Make the EU more streamlined and competitive
To get what it wants the UK believes it will need to rewrite treaties agreed by all 28 EU members.
QA: UK’s planned EU referendum
Meanwhile, the Universities UK group – whose members include 133 executive heads of UK university institutions – has said it backs Britain’s membership of the EU.
Vice-chancellors will later launch a “Yes” campaign alongside shadow business secretary Chuka Umunna and pro-European Tory MP Damian Green.
Dame Julia Goodfellow, president of Universities UK, is expected to tell the event in London they must “stand up and be counted”.
“It is abundantly clear that the UK’s membership of the European Union has an overwhelmingly positive impact on our world-leading universities, enhancing university research and teaching,” she will say.
“The case for staying in Europe is about ensuring the future prosperity of the UK, it’s about maximising the chances of new discoveries that enhance the society in which we live, it’s about the UK’s standing in the world, it’s about British jobs and it’s about opportunities for British people now and in the future.”
UKIP, which is campaigning for a “No” vote in the referendum, criticised Universities UK for entering the debate.
Deputy leader Paul Nuttall, an MEP and former university lecturer, said: “Given that universities are supposed to be the bastions of open-minded learning, it seems wrong that an institution governing the interests of British education should embroil itself in a political debate that has seen people denied any democratic say whatsoever on how Britain should be governed for 40 years.”
He said UK universities would be “far better engaging with European institutions, as they do with those in many other countries around the world, without this meaning being shackled to an outdated political system”.