The Nationals did not sign the final communique of the Glasgow climate summit that commits to doing more to cut medium-term emissions, deputy prime minister Barnaby Joyce has said, adding Australia is “happy with our targets”.

Joyce, who was campaigning in the NSW coal town of Singleton on Monday, said the government had already determined its 2030 emission reduction target, and the Nationals had not agreed to the Cop26 pact signed by the Australian government on Sunday.

“The Nationals did not sign it. I did not sign it,” Joyce told the ABC.

“I am an executive member of this government. We are happy with our targets, with the negotiations the Nationals had with the Liberals (and) we said that we wouldn’t be changing our 2030 targets.”

Joyce also targeted the president of Cop26, Alok Sharma, saying he was “cynical” about the suggestion he was emotional about the outcome of the summit.

“Give me a break. These people are not worried about the environment, they just want to end up on television,” Joyce said.

“He [Sharma] was with his gavel and ‘oh, I’m almost crying, I can’t do this’. He wants to shut down our coal industry but he never talked about shutting down the oil fields in the North Sea.”

“He wants to shut down industries in other people’s countries, not in his country.”

When asked why he was “mocking” Sharma, Joyce said he was “cynical” about the Glasgow summit.

Earlier, prime minister Scott Morrison all but ruled out adopting a more ambitious 2030 emissions reduction target, dismissing calls from moderate MPs who want Australia to revisit its commitment at next year’s UN climate summit.

Under the Glasgow pact arising from this month’s Cop26 summit, Australia was a signatory to a joint “request” for countries to re-examine and strengthen 2030 targets when countries return to the negotiating table at Cop27 in Egypt.

Morrison on Monday said Australia had no plans to change its policy but would “meet and beat” its Paris target of a 26% to 28% cut on 2005 emission levels. This was in line with a statement released on Sunday that described the 2030 target as “fixed”.

“We are going to achieve a 35% reduction in emissions by 2030. That is what we are going to achieve and that is what actually matters,” Morrison said on Monday.

“What matters is what you actually achieve. We are well above our target because our policy is to meet and beat, that is what we do.”

Australia was the only major developed country that refused to increase its 2030 emissions reduction targets at the Glasgow summit, rebuffing calls from allies and experts that stronger medium term targets are needed to prevent catastrophic global warming.

The NSW Liberal MP Dave Sharma said Australia should consider a target of 40% to 45% by 2035, building on Australia’s forecast of achieving a 35% reduction by 2030 – largely driven by state targets.

“It’s a modest stretch, but it’s not a big stretch,” Sharma told Sky News on Monday.

“Particularly when you consider the number of new technologies we’re investing in and the cost of things like battery storage that are coming down now at an exponential rate.”

Fellow moderates Jason Falinski, Katie Allen and Trent Zimmerman are also pushing for the government to revise its medium term target in the wake of the Glasgow resolution.

The Glasgow pact also included a resolution to “phase down” coal and accelerate efforts away from “unabated” coal power, but this clause was watered down after a push by the Indian delegation objected to the term “phase out”.

Sharma said the resolution indicated a clear shift “away from fossil fuels”, while Queensland Nationals senator Matt Canavan said the result was “a big green light for us to build more coal mines.”

Joyce had earlier said the government’s position on fossil fuels was clear, and Australia had different considerations as a major coal exporter.

“We will tell the Australian people quite clearly that if you stop using Australian coal, you’re just going to use more Indian coal or other coal from other parts of the world, from Indonesia, from Mongolia. And you’re going to get more emissions, not less,” Joyce said.

He said that shutting down Australia’s coal industry would lead to a drop in export earnings, a fall in the value of the Australian dollar and a rise in the cost of imports.

“If you start shutting that (coal) down, you of course are going to start shutting down your standard of living in Australia,” Joyce said.”

“We’re doing our part. We’ve always done our part, but we have to be tempered and understand quite clearly, you know, where our money … comes from.”

Morrison said he did not believe the Glasgow summit had been the “death knell” for the coal industry, saying there would be a transition but over a long period of time.

“For all those working in the industry in Australia, they will continue to work in the industry for decades to come,” Morrison said.

The Labor leader, Anthony Albanese, criticised the government for signing the Glasgow resolution but then refusing to consider a change to Australia’s 2030 target.

“I find it completely extraordinary that 24 hours after the federal government signed up to having a higher 2030 target in 2022, they’ve walked away from that commitment that they voluntarily signed up to in Glasgow,” Albanese said.

Albanese, who is expected to release Labor’s updated climate change policy later this month once the party resolves its position in the wake of the Glasgow summit, indicated Labor would be more ambitious than the Coalition.

“I’m confident that a Labor Government will tackle climate change and will join the world rather than being in the naughty corner,” he said.

“Labor will always engage with the world and will punch above our weight.”