A senior cabinet minister has accused Jeremy Corbyn of lying over leaked documents that he claims show government officials have been involved in trade talks with the United States to allow private companies access to the NHS.

Corbyn claims the documents “confirm the US is demanding the NHS is on the table” and leave the Conservatives’ claim that this is not the case “in absolute tatters”.

The 451 pages of unredacted material cover rounds of talks taking place since July 2017 and cover both medicine pricing and services, with the US apparently demanding “total market access” to the UK.

“The US is demanding that our NHS is on the in negotiations for a toxic deal – it’s already being talked about in secret. That could lead to runaway privatisation of our health service,” Corbyn told reporters at a press conference this morning.

But the international trade secretary Liz Truss hit out at Corbyn's allegations, accusing him of "getting desperate and out-and-out liying".

“People should not believe a word that he says, this stunt is simply a smokescreen for the fact that he has no plan for Brexit and that he has been forced to admit that he wants to increase taxes for millions of families,” she said in a statement.

“As we have consistently made clear, the NHS will not be on the table in any future trade deal and the price that the NHS pays for drugs will not be on the table. This sort of conspiracy theory fuelled nonsense is not befitting of the leader of a major political party.”

Meanwhile Conservative leader Boris Johnson tweeted a further denial that the health service was ‘for sale’ a hour before Corbyn made his allegations public.

“Our NHS will not be on the table for any trade negotiations,” tweeted Johnson above a picture of him walking down a hospital corridor flanked by two laughing health professionals.