Former prime ministers Kevin Rudd and Malcolm Turnbull claimed that more than 70 per cent of Australia’s trade was with countries committed to achieving net-zero greenhouse gas emissions.

In a joint opinion piece, they argued the federal government’s lack of action on emissions reduction had left the nation exposed to a number of risks, including the imposition of carbon border taxes on Australian goods.

At the time the article was published, 20 of Australia's 30 biggest trading partners had already committed to reaching net-zero emissions.

Together, these 20 countries accounted for 71.6 per cent of Australia's total two-way trade (all exports and imports).

Measured by exports alone, the proportion was even higher.

Of Australia's top 30 export destinations, 17 countries had announced commitments to net-zero emissions, accounting for 74.2 per cent of the total.

On both measures, the numbers were slightly higher again once smaller trade partners — those inside the European Union but outside the top 30 — were included.

Verdict: Mr Rudd and Mr Turnbull’s claim is a fair call.