Deputy Prime Minister Barnaby Joyce says Campbell Newman decision to quit Queensland's Liberal National Party is not politically brave and is timed to damage the party.
The former Queensland premier resigned from the LNP and his position as party trustee on Sunday after its annual conference, saying he was "dismayed" with both the state and federal arms of the party.
Mr Newman accused the LNP of failing to stand up for individual freedom and small businesses amid a "heavy-handed" response to COVID-19.
While Mr Joyce said he respected Mr Newman, he accused the former premier of lacking political valour and bravery and timing his resignation to damage the LNP.
"To be quite frank, I don't don't respect this," he told ABC Radio National on Monday.
The deputy prime minister said he would have respected Mr Newman if he had stood up to explain his decision to supporters and grassroots LNP members at the party conference rather than issuing a statement.
"To make an announcement in the middle of a conference without telling anybody is not the first move of a person who's doing something that is showing sort of some form of political bravery. It's obviously (the) timing is for damage," Mr Joyce said.
"Why would you do that to the people who formerly supported you? Now I can understand people's political views change, but the first move you make in your new political career is a reflection of the type of politics that you will follow, and the first move was: 'I'm going to kick you'."
Mr Newman accused the LNP of failing to stand up for fiscal responsibility, smaller government, support for small business, elimination of red tape and free speech and liberty.
"The last straw for me has been the destruction of people's livelihoods, jobs and freedoms under governments' heavy-handed response to COVID-19 across the nation," he said in a statement.
Mr Newman's resignation came a day after former Queensland opposition leader Lawrence Springborg was elected LNP president on Saturday.
Mr Springborg promised to end the organisational wing's interference in the LNP's parliamentary wing.
On Saturday, night Labor comfortably held onto the state seat of Stretton, in south Brisbane, in a by-election called after the death of sitting Labor MP Duncan Pegg in June.
LNP state director Tony Eyres thanked Mr Newman following his resignation on Sunday night.
"The LNP would like to wish former premier Campbell Newman all the best in his new direction," Mr Eyres said in a statement on Monday.
"On the weekend the grassroots members and the parliamentary team of the LNP made a clear decision to chart a new path of unity, laying a strong platform for the party's future and in turn the future of Queensland.
"The LNP thanks Mr and Mrs Newman for their service."
Speaking on Monday, Health Minister Yvette D'Ath says Mr Newman's exit is a decision to break ranks from the LNP.
"What I find interesting is it's not the Leader of the Opposition David Crisafulli distancing himself from Campbell Newman, it's Campbell Newman distancing himself from the Leader of the Opposition and from the LNP," she said.
Australian Associated Press