The email, issued by the Women’s Tennis Association (WTA) Player Council, claimed players who had not been fully vaccinated against coronavirus would be allowed to travel to Australia but would need to undergo two weeks of "hard quarantine".

It also revealed that players who had received two doses of a COVID-19 vaccine would not be required to isolate upon arrival and would have "complete freedom of movement" during their stay in Melbourne.

Players were asked to "keep this information confidential until the Government makes an official announcement".

The WTA Player Council said it had been "communicating regularly" with Tennis Australia over conditions facing players but was told to "wait a few days before speaking about it as they were still working with the Government on the details".

"Because Victoria’s vaccination rate will hit 80 per cent at the end of the week and 90 per cent next month, it has been confirmed that conditions for players at the Australian Open will improve significantly," the email reads.

The leaked email, obtained by freelance tennis journalist Ben Rothenberg, has added another twist to the saga over Australian Open restrictions.

Last week, Australia's Immigration Minister Alex Hawke said that anyone travelling to the country must be fully vaccinated, with no exception made for players looking to compete at the first tennis Grand Slam of 2022.

"The Government in establishing its borders has said that you'll need to be double vaccinated to visit Australia," Hawke told ABC Radio.

"That's a universal application, not just to tennis players.

"I mean that every visitor to Australia will need to be double vaccinated."

The move cast doubt over the participation of men's world number one Novak Djokovic.

The 34-year-old Serbian, who is seeking a record 21st Grand Slam men's singles title and 10th Australian Open crown, is opposed to mandatory COVID-19 vaccines and refuses to reveal his inoculation status.

Victoria's Health minister Martin Foley told ABC that he was "confident" of having the "world’s best field here" and the "world’s best tournament early next year".

"We don’t control the borders, we don’t issue the visas," said Foley.

"The Commonwealth does that.

"We’ll work in partnership with them and the Australian Open to make sure that we have a cracker of an Australian Open in 2022."

Victoria’s Major Events Minister Martin Pakula said the vaccination conditions were "not settled yet".

"We’re still talking to the Commonwealth about whether the rule for international unvaccinated arrivals is either 14 days quarantine or they’re not coming into the country at all," Pakula told ABC.

Recent figures reportedly found that that more than a third of players on the men's and women's tour are not double jabbed.

But Pakula added: "I understand from my chat with Craig Tiley [chief executive of  Tennis Australia] this morning that the vax rate for players is rising pretty quickly now and it's near enough to 80 per cent."

Responding to the leaked email, Tennis Australia said it was working with the state and federal authorities on the COVID-19 conditions.

"Everyone has been buoyed by the easing of restrictions over the past week, along with the Premier's announcement yesterday that large crowds will be welcomed back to events next year," said Tennis Australia.

"We are optimistic that we can hold the Australian Open as close to pre-pandemic conditions as possible."

This year’s Australian Open was postponed by three weeks with players having to undergo a 14-day hotel quarantine period upon arrival.

It was also partly staged behind closed doors due to a state-wide lockdown being imposed in Victoria.

Next year's Australian Open is scheduled to be held from January 17 to 30.