An outspoken Coalition senator has been blasted by senior colleagues after a tone-deaf tweet about the chaos unfolding in Afghanistan.

The Taliban swept into Kabul on Sunday, declaring the war in Afghanistan over after insurgents took control of the presidential palace, US-led forces departed and Western nations scrambled to remove their citizens.

President Ashraf Ghani fled the country as the Islamist militants entered the city, saying he wanted to avoid bloodshed, while hundreds of Afghans desperate to leave flooded Kabul airport.

There are grave fears for the safety of hundreds of Afghans who helped allied forces, including Australia, over the two-decade combat effort and who remain stuck in the embattled country.

On Monday, Cabinet’s national security committee met to assess the situation, with Australian air force planes expected to be deployed to Kabul.

Prime Minister Scott Morrison refused to comment on whether the Taliban’s lightning advance through Afghanistan had upended rescue plans.

But Queensland LNP senator Matt Canavan was less reticent, storking anger among his colleagues with a social media post on Monday.

“Does anyone know whether the Taliban will sign up for net zero,” he tweeted.

Tweet from @M_McCormackMP

Senator Canavan, a former cabinet minister, is a notorious opponent of climate action and has said he would cross the floor to vote against a policy of net-zero emissions.

He is a huge advocate for the coal industry and his Twitter profile picture shows him in high-vis workwear, with his face covered in coal dust.

However, his pre-political career consisted of work at the Productivity Commission and for consultants KPMG. Senator Canavan is also a former chief of staff to Nationals leader Barnaby Joyce.

Monday’s tweet drew a swift response from the man Mr Joyce replaced in the Nationals top job, Michael McCormack, who said it was “disappointing, insensitive and unnecessary”.

“To compare climate policy with the bloodshed on the streets of Kabul is out of place and unworthy of a member of the Australian parliament,” Mr McCormack wrote on Twitter.

“Our thoughts today should be for the Afghan people and the families of our brave fallen Diggers.”

Another Nationals MP, Darren Chester, also weighed in. Mr Chester was minister for veterans affairs until losing the job in the reshuffle after Mr Joyce returned to the Nationals leadership.

“Matt Canavan doesn’t speak for me,” Mr Chester tweeted.

“This tweet is offensive, disrespectful and totally lacking in any compassion for the 41 brave Australians who lost their lives, the families who grieve for them, the 39,000 Australians who served in this conflict, and the people of Afghanistan.”

Earlier, Prime Minister Scott Morrison said the 41 Australians who died in Afghanistan had been fighting for freedom, which he believe was always worth it regardless of the outcome.

“The reason we went there was to track down Osama bin Laden. The reason we went there was to stop al-Qaeda and stop them mounting operations from there,” Mr Morrison said.

Since 2013, Australia has granted visas to 1800 people who worked with its forces out of Afghanistan.

The US sent about 3000 extra troops to evacuate embassy staff and others as the capital fell.

Britain has also said it is deploying troops to help its nationals and local translators flee.

-with AAP