Nigel Farage and Paul Nuttall. Christopher Furlong/Getty Images LONDON — UKIP is coming under increasing pressure to respond to claims that they believe in privatising the National Health Service.

On Question Time this week, the party's Deputy Leader Peter Whittle denied that the party had ever been in favour of NHS privatisation.

Responding to the attacks on Whittle, the party tweeted on Thursday that "UKIP has never and will never enter any election calling for the privatisation of the NHS. Full stop."

So is it true? Well, not quite.

While the party has distanced itself from NHS privatisation in recent years, they have previously been much more open about the idea.

UKIP's 2005 manifesto

UKIP's 2005 general election manifesto acknowledges that the 'principle' of a free NHS remained popular. However, it then goes on to note that compared to other developed countries "our proportion of privately funded healthcare is lower."

It then goes on: "Private health insurance schemes similar to those in France, Germany and several other countries might provide a valuable supplement to NHS resources."

Paul Nuttall

UKIP leader Paul Nuttall now states that he is committed to a free NHS. In an interview with Business Insider last month, the Merseysider said: "privatisation in the NHS hasn't worked."

However, in 2011 he told an election hustings that the NHS is "a monolithic hangover from days gone by."

He added: "I would like to see more free market introduced into the NHS."

In now-deleted blog posts on his personal website, he also called for the country to discard its attachment to the "sacred cow" of the NHS.

"I would like to congratulate the coalition government for bringing a whiff of privatisation into the beleaguered National Health Service," he wrote.

"I would argue that the very existence of the NHS stifles competition, and as competition drives quality and choice, innovation and improvements are restricted.

"Therefore, I believe, as long as the NHS is the 'sacred cow' of British politics, the longer the British people will suffer with a second rate health service."

Asked in December about the posts, Nuttall told Andrew Marr that he would protect the NHS as Ukip leader, but added that "at some point we have to have a debate about how we fund the NHS."

Nigel Farage

Former UKIP leader Nigel Farage also has a record of backing NHS privatisation.

"I think we’re going to have to think about healthcare very, very differently, " he said in 2012.

"I think we are going to have to move to an insurance-based system of healthcare."

He went on: "Frankly, I would feel more comfortable that my money would return value if I was able to do that through the market place of an insurance company than just us trustingly giving £100bn a year to central government and expecting them to organise the healthcare service from cradle to grave for us."

Arron Banks

One of the central messages of the pro-Brexit campaign was that leaving the EU would make more money available for the NHS. However, Ukip's biggest donor and the head of the Leave.EU campaign, Arron Banks, told an American audience last year that he really wanted the health service to be sold off. "If it were up to me, I’d privatize the NHS," he told the Cato Institute in Washington.

NHS is 'very hard to get rid of'

UKIP's then general secretary Matthew Richardson told another audience in Washington in 2015, that he also wanted Britain's free to use health service sold off. However, he accepted that doing so would be difficult.

“A number I couldn't possibly imagine when I was younger is now the amount of money that is owed by my country," Richardson said.

"Of course, at the heart of this, the Reichstag bunker of socialism, is the National Health Service.

"And that is why socialised health care is so dangerous – because it is a ratchet. Once it is in place it is very, very hard to get rid of."

At another event in the city he added: "The biggest waste of money of course in the United Kingdom is the NHS."

A long-term project

While most senior UKIP figures accept that it will be very difficult to get rid of the NHS, many still hold on to the ambition. In 2012, leaked documents from a UKIP executive meeting revealed that the party still desire a more "radical" approach to the NHS, than their official policy suggests.

While agreeing that studies should be commissioned into privatising the service, the members agreed that it was a long-term project.

"In the longer term we want a radical approach but we cannot do that in this time frame," they concluded.