State premiers, who know what damage a closed international border is doing economically, will still “play their trump card” in protest of any plan to reopen Australia, says Sky News host Chris Smith.

It comes as a federal plan is “being devised” to reopen Australia’s international border and use Singapore as the “quarantine gateway”, according to Mr Smith.

“The plan would involve making Singapore our vaccination hub and ensure that anyone who came to Australia had to depart from Singapore … and they need to produce a digital vaccination certificate,” he said.

He spoke of WA Premier Mark McGowan, and Queensland Premier Annastacia Palaszczuk’s “trump card”, which involves shutting borders “every time someone sneezed” and trying to entirely eradicate COVID-19.

“McGowan played that trump card, as did Annastacia Palaszczuk in Queensland late last year, perfectly.”

Mr Smith said the plan to reopen Australia’s international border is an “outstanding concept”, but those who are risk-averse “won’t be happy, Jan.”

“But this will be our future – getting a vaccine, and using a vaccine certificate to travel, do business and keep Australia’s economy alive.”