Britain's Prime Minister David Cameron appears on the Marr Show on the BBC, in London, Britain, June 12, 2016. [Photo/Agencies]

LONDON - Pensions and the publicly funded National Health Service could face cuts if Britons vote to leave the European Union, Prime Minister David Cameron told a Sunday newspaper, seeking to win support from some of the most pro-Brexit members of the public.

Polls, which show Britons are evenly divided ahead of a June 23 referendum on EU membership, also indicate the elderly are among the most likely to turn out on polling day and are also among the most eurosceptic voters.

With less than two weeks until the vote, Cameron warned that annual pension increases, free television licences and bus passes could all be cut to make up for a "black hole" in the public finances, the Observer newspaper reported.

"You would have to start cutting things that people really value, whether it is the money going to the NHS or whether it is support for our pension system," Cameron was quoted as saying.

But in a sign of increasing division within Cameron's ruling Conservative Party, a former minister and prominent 'Leave' campaigner accused him of making a "a baseless threat".

"What we now have is a vindictive and desperate attempt to bully and frighten the British people - particularly pensioners - all in a frantic bid to rescue a failing campaign," Iain Duncan Smith said, in an emailed statement from the 'Leave' campaign.