Godolphin trainer John O'Shea says a significant prize money boost has positioned The Metropolitan to become a major lead-up race to the Melbourne Cup.

The Group One staying feature, run at Randwick on the first Saturday in October, will carry a $750,000 purse from this year, an increase of $350,000.

And now that Canterbury racecourse has approval as a quarantine training facility for overseas horses, O'Shea expects The Metropolitan to become an attractive option for the international raiders.

"We now have a quarantine centre here so I think it will take on international significance," O'Shea said.

"Some of those Melbourne Cup hopefuls can run for $750,000 here a month out from the Melbourne Cup instead of racing for a ribbon and a meat pie in England a month out from the Melbourne Cup."

Canterbury won't be operational as a quarantine facility this spring as it is needed for race meetings until the beleaguered Kensington circuit is reopened.

However, Australian Turf Club chief executive Darren Pearce said it was an option in the future and revealed there had already been inquiries from Japan about the possibility of using Canterbury as a quarantine and training base for their spring carnival horses.

The boost to The Metropolitan was announced this week as part of a more than $2 million financial injection by the ATC into the Sydney spring carnival prize money coffers.

The Epsom Handicap has doubled in value to $1 million, a move set to entice premier trainer Chris Waller to keep some of his best horses in Sydney for longer, including Doncaster Mile winner Kermadec.

"A horse like Kermadec, he can stay at home a bit later now and run in the Epsom," Waller said.

"And then Sydney gets the chance to look at a pretty good horse."

Godolphin also plans to have a strong presence in the feature mile with Sweynesse and It's Somewhat among their horses in the mix.

Weight-for-age star Contributer, who will be nominated for the Hong Kong international meeting in December, is set to campaign exclusively in Melbourne this spring with the Cox Plate his main goal.