In a Sunday Telegraph article today, Mr Cameron insisted that only the Conservatives can deliver reform in the EU and a referendum.
Speaking about Conservative party rivals for the European election, David Cameron referenced Dad's Army character Private Frazer:
There are politicians who refuse to be upbeat about Britain.
To them, pessimism equals patriotism.
They insist that our best days are behind us and that everything is bound to get worse.
Like Private Frazer politicians they're perennially crying out that 'we're all doomed'.
More top news
The Indonesian police plane dropped out of contact and villagers have 'found police uniforms' in the sea.
The Post Office said it was 'business as usual' but unions said Saturday's industrial action was getting solid support.
A former German prisoner of war has left nearly £400,000 to a small Scottish village for the kindness shown to him during his captivity.