Treasurer Michael O'Brien announced a surprise $184 million levy on Crown's 2,500 pokies at the last budget, which sparked a nine-month consultation with the casino giant.

Crown confirmed Friday morning that it would receive an extension on its Melbourne casino licence to 2050, from its current 2033 expiry.

Crown will also receive approval to buy more poker machine licences for its main gaming floor in Melbourne. The number of poker machines across the state will not increase above the current level of 30,000 because Crown will buy entitlements from pub and club operators, many of whom have complained that the cost of servicing debt to buy the machines is oppressive.

Although the concession will boost certainty around the company's licence, investors will also scour the deal to see if  Crown was able to secure a lower tax rate charged on revenue from high rollers.

Crown has been pushing for a cut in its VIP tax rate, saying the progressive regime in Victoria hurts its ability to compete against casinos in other states.

The Victorian rate starts at 10 per cent and increases with revenue from VIP program players - those gamblers from overseas or interstate who commit to gambling tens of thousands of dollars up front.

At its full-year results last week Crown unveiled a net profit that soared 35.2 percentage points to $646 million.

The poker machine levy first outlined in December 2013 was to be an annual levy of $5550 per machine this financial year and then rise to $22,715 per machine in 2014. Crown would also potentially be allowed to drop its player return ratio from 87 per cent to 85 per cent.

Shadow Treasurer Tim Pallas said the deal was an embarrassment for the government.

"The government was forced into a backdown over their botched efforts to introduce an extra charge on Crown. 'They have negotiated under duress and it looks like Crown have taken the Victorian government to the cleaners," he said.

Greens Leader Greg Barber, whose party is likely to hold the balance of power in the Upper House after the election, said the move would require legislation before the November 29 election.

"There is just this little thing called Parliament they need to deal with," he said.

Neither Crown nor the government would comment.