Lottery operator Camelot should be allowed to hang on to its monopoly, an influential committee of MPs has said.
Tessa Jowell wants a shake-up
The Commons Culture Committee also called for the abolition of the tax the government receives on sales of National Lottery tickets.
Culture Secretary Tessa Jowell last year called for a big shake-up of the way the lottery licence is awarded - including introducing rival operators.
But the MPs said Camelot's monopoly was "the lesser of two evils".
'More work' needed
Introducing rival operators would only "destabilise" the system and put cash for good causes at risk, the committee warned.
Competitive tendering by a single licence-holder "would effectively introduce the attractive elements of competition to the National Lottery without the uncertainty associated with a multiple licence system," it said.
The committee backed the government's view that more should be done to stimulate competition for the next lottery licence in 2009.
But it said "far more work" needed to be done for the government to demonstrate its proposals were workable.
Moira Black, chairman of the lottery regulator the National Lottery Commission, said she welcomed the reports findings.
But she added: "A further review of the government's proposals will take time.
"If the legislation is delayed significantly, any flexibility might well be introduced too late for us to use effectively in the next competition."
In its report, the Culture Committee accused ministers of "eroding" their pledge not to use lottery cash to replace public spending.
It said the £1.5bn earmarked for Britain's Olympic bid was a "straightforward raid" of lottery funds.
The government has proposed a national lottery day and plaques on lottery-funded buildings to boost sales.
But the Culture Committee said dropping the 12% Lottery Duty would have more effect.
Of every pound spent on a lottery ticket, 28p goes to the good causes and 50p goes in prizes to attract people to play the games.
But 12p in every pound goes to the government in the form of Lottery Duty.
The tax has swelled the Treasury's coffers by more than £5bn since the lottery began nearly ten years ago.
The Culture Committee say this represents a "double hit" on the money paid by lottery players because much of the money that goes to good causes is in line with government priorities.
It says abolishing Lottery duty would boost the Lottery by making more money available for prizes and good causes, encouraging more people to play and keep playing.
"A concrete commitment by the government of this kind is likely to do more for the promotion of the Lottery as a `good thing' amongst the public than any amount of plaques and open days," the committee said.
The Department of Culture Media and Sport said it "welcomed" the committee's findings and would be producing a full response in due course.