Ex-military chiefs are facing the threat of being barred from contact with ministers and defence officials after several were secretly filmed claiming to be able to exert influence on behalf of arms firms.
Defence Secretary Philip Hammond said that if an MoD inquiry found the senior figures had abused the access that came with their previous high rank then it could be "shut down" in future.
And the future of one senior figure as the figurehead of the Royal British Legion has come under review by the charity after he was alleged to have told undercover reporters his role could help bypass restrictions.
Labour demanded "full disclosure" of any dealings between those caught by the Sunday Times sting and ministers, personnel and officials dealing with defence contracts.
But while Mr Hammond said the revelations were "deeply damaging" to the reputations of the individuals concerned, he insisted there was "no way that retired officers influence the way that military equipment is procured".
Undercover reporters posing as representatives of a South Korean weapons manufacturer seeking to sell unmanned "drone" aircraft to the UK Government set up and filmed meetings with the senior ex-military figures. The newspaper said two - former Defence Academy head Lieutenant General Sir John Kiszely and former MoD procurement chief Lieutenant General Richard Applegate - claimed to have lobbied on deals in breach of Whitehall rules.
Retiring officers are subject to a two-year "purdah" period after leaving public service during which they cannot take on private sector roles related to their previous job. Admiral Sir Trevor Soar, commander-in-chief fleet of the Royal Navy until earlier this year, is alleged to have said he could simply "ignore" the two-year ban because the enforcement system was ineffective. And ex-head of the Army Lord Dannatt claimed he could speak to the MoD's top civil servant, a former school friend.
All deny breaking any rules, the newspaper said, and insist they had the best interests of the military at heart.
On top of the MoD investigation, the report also prompted a high-level review by the Legion into whether Sir John, a decorated Falklands hero, had abused his position with the charity. He is alleged to have said he could push the fake firm's interests to figures such as the Prime Minister in a private box at the Festival of Remembrance next month at the Royal Albert Hall.
Sir John told the Sunday Times he had always kept his commercial interests "entirely separate" from his role with the Legion and had never used access gained through it to discuss any business interests.