Members of the Commons Select Committee on Health said plans to allow smoking in private clubs and pubs that did not serve food were "unfair, unjust and unworkable".
The MPs called for ministers to impose a full ban on smoking in all public places, including military bases and prisons, saying that the proposed exemptions to a ban represented "a recipe for chaos".
The committee's chairman, the Labour MP Kevin Barron, took a sideswipe yesterday at the Defence Secretary, John Reid, who led a cabinet battle against a full ban. Mr Barron warned: "The case is one of protecting political egos, not protecting public health."
In a strongly worded report, the all-party committee condemned the Government for its "muddled and vacillating" response to the debate about smoking. Its report said: "The exemption for clubs and pubs where food is not served is illogical. It means that workers who are most exposed to second-hand smoke, and therefore most at risk, will not be protected. We have sought from the Government a convincing rationale for this, but have not found one. It defies logic."
Ninety-five MPs, including 64 Labour backbenchers, have signed a parliamentary motion calling for a free vote, while 89 MPs, including 53 Labour, have signed up to a motion supporting a complete ban.
The chief medical officer, Sir Liam Donaldson, also revealed that he threatened to resign after his advice on the issue was ignored.
Mr Barron declared that it would be "very difficult" for MPs to back a partial ban, given the strong evidence in favour of a total prohibition on smoking in public places.
He said: "The Government is missing out on a golden opportunity to dramatically improve the public health of this country. The current proposals fly in the face of medical opinion and will do nothing to protect those most at risk.
"Only a total ban will protect the public from the lethal effects of passive smoking and ensure that people can work in an environment which is not dangerous to their health."
The report contrasted the experience of Britain with that in Ireland, where a full smoking ban has been brought into force. It warned: "Political support for a smoking ban in the Republic of Ireland is in stark contrast to the approach of the UK Government, which has been muddled and vacillating.
"Policy towards the control of smoking in public places and workplaces has been a litany of good intentions undermined by faint-heartedness."
The Conservative MP Anne Milton said: "This is the worst possible solution to this. It would almost be better to do nothing. Nobody, absolutely nobody, wants the partial ban."