He also wants to make sure Britain will be involved in economic decisions of the 19-member eurozone so it can protect British interests, and be also protected from political integration.
The most controversial point of Cameron’s proposals is to cut in-work benefits for EU migrants during their first four years in Britain.
Concerns have been raised that this could harm the EU’s core value of freedom of movement.
Eastern European member states, that have seen large number of workers migrating to Britain for work, have been reluctant to sign up, arguing that Cameron’s proposal is discriminatory.
Germany’s backing is crucial to the UK getting the deal on migration and welfare.
Merkel has said last month, “we will not put the fundamental achievements of European integration in question, in particular, the principles of freedom of movement and non-discrimination of European citizens,” AFP reported.
Cameron argued in Bild that the UK was not questioning the freedom of movement.
“We want to stop people taking out from a welfare system without contributing to it first,” he wrote.
“Like Germany, Britain believes in the principle of free movement of workers. But that should not mean the current freedom to claim all benefits from day one and that’s why I’ve proposed restricting this for the first four years,” Cameron argued.
He suggested that curbing migrants’ benefits would make a “big difference” to whether the UK stayed.
Cameron is later due to travel to Hungary for talks with prime minister Viktor Orban, who on Wednesday met with the head of Poland’s ruling Law and Justice party, Jaroslaw Kaczynski, and Polish prime minister Beata Szydlo.
As the campaign ahead of the referendum heats up, a new UK cross-party campaign group is pushing for an EU exit.
Conservative MPs Peter Bone and Tom Pursglove, Labour’s Kate Hoey and UKIP Leader Nigel Farage will announce the formation of Grassroots Out at a series of public events, the BBC reported.