David Cameron is holding talks with the German Chancellor Angela Merkel in Berlin today - someone he needs to win over if he is to have any chance of pushing his EU reform plans through.
He is also due to meet the Polish Prime Minister today, as he wraps up his bid to renegotiate the terms of the UK's membership of the European Union with key leaders.
The Prime Minister has met French President Francois Hollande in Paris to discuss potential changes to the EU treaty which he says could benefit both countries.
Describing France as an "essential and valued partner of Britain", David Cameron said the two countries might have different priorities, but similar aims for the future, and said he hoped they could reach an agreement - including on issues such as tackling extremism and climate change.
David Cameron has begun a whirlwind tour of Europe to discuss his terms for renegotiating the UK's membership of the EU with key leaders.
Prime Minister plans a whistle-stop charm offensive with EU leaders this week.
Details of the In/Out referendum will be presented to Parliament in a Bill this morning.