David Cameron will discuss the UK's EU renegotiation with French President Francois Hollande in Paris later, ahead of this week's crucial summit.
The PM is ramping up his diplomatic push, with the French government said to be concerned about UK calls for protection for non-eurozone countries.
Securing French agreement will be vital if EU leaders are to agree a deal at the summit on Thursday and Friday.
No 10 said the French had shown "willingness" to find a solution.
Mr Cameron - who met German Chancellor Angela Merkel for talks on Friday - will also address senior MEPs to discuss the proposed reform package in Brussels on Tuesday.