The International Olympic Committee (IOC) on Thursday issued a sharp warning to the private club set to host golf at the 2020 Tokyo Games: admit women or you're out.

On a visit to Tokyo to check on the city's Olympic preparations, IOC vice president John Coates said the Kasumigaseki Country Club in Saitama prefecture was running out of time to change its policy of refusing to grant full membership to women.

"Our principles are based on non-discrimination, that's the position we've made quite clear," Coates, chairman of the coordination commission which oversees preparations for the Olympics, told reporters.

"There has been progress -- as recently as this week there have been more discussions with the club (to suggest) it's heading in the right direction for them to have a non-discriminatory membership procedure," he added, flagging the end of June as a possible time frame to resolve the awkward standoff.

Earlier this month, the club's chairman told local media he was "flummoxed" by the row, prompting further criticism of its policies.

Coates insisted, however, that if the current impasse dragged on beyond June, the IOC would be forced to look for alternative venues.

"At some point there has to be a cut-off," said the Australian, adding that there was still plenty of time to find another golf club.

"We've got to be very careful because we are going there by their grace. I respect that it's a private club but our position is clear. We will only go to a club that has non-discrimination."

'Considerable savings'

Coates also sought to allay fears over the Games budget, which experts warn could reach an eye-watering $25 billion, by pointing to "considerable savings" made by moving some of the venues outside of Tokyo.

In its bid, Tokyo estimated the bill for the Games at a little over $7 million and promised 85 percent of venues would be within eight kilometres (five miles) of the Olympic village, plans long since torn up due to soaring costs.

"As a result of looking at existing venues outside of Tokyo, we have saved $2.2 billion," said Coates, referring to sports such as cycling, basketball and sailing, which be hosted by cities outside of the capital.

"There's been no pushback at all. We all have the same goal -- to deliver a successful Olympic Games."

Meanwhile, the head of the local organising committee wants the host nation to play their opening game of the Olympic baseball competition in Fukushima, site of nuclear disasters six years ago.

"Ideally we would like to see Japan to play their first game in Fukushima as a symbol of the region’s recovery," said Yoshiro Mori. "We hope to be able to go into more detail on the proposal soon."

Tokyo officials insist Fukushima -- located some 240 kilometres (150 miles) from Tokyo -- is safe, while world baseball officials have also agreed it posed no threat to players.

The March 2011 tsunami killed around 18,000 people and swamped emergency power supplies at the Fukushima nuclear plant, sending its reactors into meltdown.