Senior minister Greg Hunt has refused to say whether Australia under a Morrison government will update its 2030 emissions target as required under the Glasgow Cop26 agreement and instead quoted Shakespeare.

But separately, the foreign minister and emissions reduction minister said in a joint statement on Sunday: “Australia’s 2030 target is fixed and we are committed to meeting and beating it, as we did with our Kyoto-era targets.”

Hunt dodged a series of questions on the issue from host David Speers when appearing on the ABC’s Insiders program.

He said Australia “welcomed the outcome at Glasgow” as “important progress for the world” but would not answer questions on whether Australia would update its 2030 target next year.

“We’re projecting a minus 35% actual pathway. So we are meeting and beating our targets,” Hunt said.

When pressed again by Speers on whether Australia would update the target in 2022 as required, he said: “We’ve set our target. But what we’ll continue to do is update our projections.”

Asked again, the minister quoted Shakesepare: “It reminds me of Prince Hal to Hotspur in Henry IV – ‘I never promised to pay thee, but now that I’m here, I’ll pay thee double’. It means under-promise and over-deliver.”

Hunt was the environment minister at the time Australia’s target of a 26-28% reduction on 2005 emissions was set under the Abbott government. Australia was one of the few nations at the Cop26 conference not to increase its short-term pledge, rejecting calls from allies in the Pacific and Europe, the US and Britain.

Sunday’s official statement from the foreign minister, Marise Payne, and the emissions reduction minister, Angus Taylor – who went to Glasgow spruiking Australia’s fossil fuel industry – makes no mention of Australia updating its 2030 target.

“The Morrison government will always stand up for and make decisions in Australia’s national interest, and we will do what’s right for rural and regional communities,” Payne and Taylor said.

“Under our plan to achieve net zero emissions by 2050, we will act in a practical, responsible way to reduce emissions and build on our track record of achievement – reducing emissions while growing our economy, maintaining affordable, reliable energy and ensuring our regions remain strong. That’s the Australian way.”

The Intergovernmental Panel on Climate Change has previously said emissions must be cut by 45% by 2030 compared with 2010 levels to limit global warming to 1.5C.

But Australia took nothing concrete on 2030 to the Glasgow summit, only committing to net zero emissions by 2050, a pledge most developed nations had made years ago. Since then, the Morrison government has released the modelling it used to make that commitment and convince its junior coalition partner, the Nationals, to support the bare minimum of action.

It sets out Australia is on track to reach net 85% emissions reduction under the Morrison government plan, with a reliance on yet to be developed technologies to take care of the final 15%, as well as laying out a bigger fossil fuel gas industry for 2050 than exists today.

Australia has signed the final agreement, which sets out countries returning next year, with updated 2030 emissions reductions targets. At the final Glasgow press conference, Cop26 president Alok Sharma was asked what would happen if nations like Australia failed to update their targets.

He said on Sunday: “All countries have signed up to this and at the end of the day this is an international agreement and every country will be judged by whether or not they stuck to the commitments they’ve made.”