'New Day', launched by the Trinity Mirror Group, publishers of 'Daily Mirror' and 'Sunday Mirror' newspapers, is the first "standalone daily national newspaper" to be launched in the country.
"The choice is clear: between a greater Britain and the great unknown. I hope readers will choose certainty and prosperity over speculation and risk. Then we can carry on making this great country greater still," Cameron wrote in reference to the referendum on June 23 when the British public will vote on whether to stay in or leave the European Union (EU).
Two million copies of 'New Day' are being distributed free on Monday. From Tuesday, it will cost 25p for two weeks before rising to 50p.
Trinity Mirror Group hopes to sell about 200,000 copies a day.
The editor, Alison Phillips, who previously headed the 'Sunday Mirror' and 'Sunday People' at the group, said the 'New Day' was predicated on an alternative way of thinking about how a newspaper should work.
The newspaper has no dedicated website and has just 25 staff, something the publisher hopes could make it profitable quickly.
It is the first new national paper since the launch of 'i', a slimmed-down version of the 'Independent' which went on sale in October 2010.
Simon Fox, chief executive of Trinity Mirror, said: "Over a million people have stopped buying a newspaper in the past two years but we believe a large number of them can be tempted back with the right product".
"Revitalising print is a core part of our strategy in parallel with digital transformation and there doesn't have to be a choice between the two - newspapers can live in the digital age if they have been designed to offer something different," Fox said.
The newspaper describes itself as "upbeat" and "politically neutral".
