Whitehall officials encouraged a health service boss to strengthen a letter that raised concerns over whether striking junior doctors would be available to respond in the event of a Paris-style attack, it has been claimed.
Emails reveal that Sir Bruce Keogh's letter went through a number of revisions to ensure concerns about the possible impact of a major incident during the walk out were made as "hard-edged" as possible, according to the Independent.
Health Secretary Jeremy Hunt was also given approval of the text, emails between the Department of Health (DoH) and the national medical director of NHS England reveal.
Liberal Democrats warned the revelations raised "serious concerns about potential political interference" and suggested that trust between the government and doctors would be damaged further, the Press Association reports.
Talks between the Government and the British Medical Association (BMA) aimed at resolving a dispute over a new contract for junior doctors are set to resume today ahead of three spells of strike action.
In an email sent the day before the first strike was declared, a DoH official told Sir Bruce the risk of a "major incident" would be "pressed quite hard in the media once the strike is formally announced" and he was advised that "the more hard-edged you can be on this, the better", according to the newspaper.
Mr Hunt agreed Sir Bruce would not be asked to speak to the media on the day the strike was declared "so long as" his letter underlined his opposition to the walk out, it added.
Asked to confirm he was "happy" with changes, an official told the health service chief: "I am sure then that JH [Jeremy Hunt] will be interested to see the proposed final product; my hope is that if you are happy to make these changes we will be able to get him over the line."
The department insisted it was "absolutely right" that ministers insisted on Sir Bruce giving his "independent" view on how the health service would be able to respond.
But Lib Dem health spokesman Norman Lamb raised concerns about political interference.
He said: "This revelation raises serious concerns about potential political interference with the independent medical director of NHS England.
"Jeremy Hunt must explain exactly who was involved in toughening up of language in this letter. My fear is that this will damage trust between the Government and junior doctors still further.
"We need a cross party commission to look at how we secure the long term future of the NHS and social care, but Jeremy Hunt must now immediately get back around the negotiating table and resolve this dispute with junior doctors that are such an integral part of our NHS."
A Department of Health spokesman said: "Industrial action of the kind planned by the BMA creates a major safety risk for patients so it was absolutely right that ministers insisted on Sir Bruce Keogh giving his independent view of the NHS' capacity to respond in the event of a major terrorist incident."