Beaconsfield MP Dominic Grieve has laughed off claims made by a large union that his voting on NHS privatisation is biased because of his involvement in a number of private healthcare companies.

The former Attorney General said an investigation exploring the links of more than 70 coalition MPs to private healthcare companies is “a complete load of twaddle”.

This week, the union Unite released details of their exploration into the interest of a number of MPs, including Mr Grieve.

The South Bucks politician is a shareholder with a number of companies including NHS drug-supplier Reckitt Benckiser, health insurer Standard Chartered and pharmaceutical giants GlaxoSmithKline and AstraZeneca.

Unite now claim many MPs who are voting to “sell-off the NHS” have an unfair interest in the success of the companies.

But this has been strongly refuted by Mr Grieve, who said the suggestion it would affect his judgement on the NHS is perverse.

He said: “What a complete load of twaddle, I mean really if that is Unite’s best point.

“Look, I am a shareholder, I have shares in British companies as lots of people do and I declare those interests on the list.

“I am not a director, I am not a majority shareholder, I have other shares in all sorts of UK companies, I mean if they were right on this then nobody ought to invest in any UK company whatsoever.

“The idea that it would influence my view in some perverse way, away from what I see is the public interest in maintaining the NHS, is just ridiculous.”

He added: “It is also party policy. Somebody could come forward and argue that they don’t think the NHS should be continued, but it is not Conservative party policy, it never has been.

“Unite might be in a position to make an argument if they could credibly put forward an argument that there was a Conservative policy to privatise the NHS, but there isn’t, there never has been.”

A statement from Unite said their research continues to reveal coalition MPs and peers who are linked to firms which stood to benefit from the sell-off, but voted for the bill.

Unite general secretary Len McCluskey, said: “The Government had no mandate to sell-off our NHS, no one voted for it, yet they are doing just that. You have to ask yourself why?

“From lobbying links to investments, and in some cases direct donations, it is clear that many MPs who supported the NHS sell-off had links to the very private healthcare companies which stood to profit.

“Since the vote to sell off our NHS, over £13 billion pounds of our local services have fallen into private hands.”