The Lower House of Federal Parliament has passed legislation allowing the Government to keep the money it has already collected from the extra tax on alcopops.

The Government says the legislation will prevent more than $400 million from being returned to distillers.

Earlier this year Health Minister Nicola Roxon indicated the Government would not try to keep the money.

The Opposition's health spokesman, Peter Dutton, says today's vote is an embarrassing backflip for the Government.

"At the time of the last sitting period, we offered to the Government the opportunity to validate the collection of the taxes," he said.

"Well, here we are today - the Minister offering up the same legislation that we were proposing seven or eight weeks ago."

Tax validation

Today the Government wants both houses to pass the legislation to validate the already collected alcopops tax.

Ms Roxon says it is vital the money is not returned to the alcohol industry.

"The Government has collected now nearly $424 million in revenue," she said.

"That would be a $424 million jackpot to the distillers if this bill is not passed today."

The Opposition has already pledged support for the measure, while the Greens and independent senators Nick Xenophon and Steve Fielding are also expected to vote in favour of the bill.

Permanent increase

However, the Government is also planning to introduce legislation in a few weeks to make the tax increase permanent.

Senator Fielding says he is unimpressed.

"The Government's got to stop hiding behind a blatant tax grab," he said.

Mr Dutton says the Government needs to prove it is serious about tackling binge drinking.

"If the Government's got the guts to do it, we'll support it," he said.

He says the Coalition has not yet seen the Government's plan.