David Cameron said leaving the EU would threaten Britain's "economic and national security".
The Prime Minister said Britain's new deal offered the "best of both worlds", while leaving the EU would be a "leap in the dark".
Cameron; individual cabinet ministers can campaign as they wish in a personal capacity.
Cameron; Leaving Europe would threaten our economic and national security.
David Cameron has warned that Britain has "100 days to secure our future", as a poll suggests the final result hangs in the balance.
The EU referendum is a choice between "the devil and the deep blue sea", one of the UK's most senior business leaders is to say today.
Britain's car industry is an economic success story, and with uncertainty over the impact of Brexit, it wants to stay put.