Malcolm Turnbull has declared he is going to be prime minister for a very long time, delivering a warning to his critics that he will not be forced out of his job.

He has faced a week of internal tensions after a series of interviews and speeches from former prime minister Tony Abbott.

But Mr Turnbull said this morning he would be running in the 2019 election and would win.

"I can assure you I will be prime minister for many, many years to come," he said.

"So that's my commitment."

In a weekend interview, Mr Turnbull said he would quit parliament when he lost the prime ministership.

That was interpreted by some as a threat to create a by-election if he was ousted from the leadership and also a suggestion that Mr Abbott should retire from Parliament.

But today Mr Turnbull has repeatedly stressed he intends to be prime minister for years.

"I know you may think that at 62 I am too old. I can assure you, I will be prime minister for a very long time," he told reporters.

Australians not focussed on 'political gossip': Turnbull

Acting Labor leader Tanya Plibersek said infighting within the Coalition would be consuming "way too much of the PM's intellectual and emotional energy and it is not good for the country".

Mr Turnbull insisted he was focussed on governing.

He deflected questions about the tussle with Mr Abbott, saying he was not interested in personalities but only the interests of 24 million Australians.

"I am focussed on my job, I am not interested in political gossip and you know something, Australians aren't either," he said.

Some of his senior colleagues this morning tacked Mr Abbott's recent comments.

Education Minister Simon Birmingham took a swipe at the former prime minister's push for changes inside the Liberal Party.

Mr Abbott wants New South Wales Liberal Party members to have a say in the preselection of candidates.

He gave a speech about the issue at a meeting over the weekend — one of many speeches and interviews he gave last week.

Senator Birmingham said similar party changes had been made in South Australia, but the results had been modest.

"It hasn't made the world of difference to membership numbers in the period since," Senator Birmingham said.

"It's a reasonable internal debate to have but I don't think anybody should overegg this debate as fixing all the problems of people's engagement in modern politics."

Industry Minister Arthur Sinodinos again emphasised Mr Abbott was entitled to speak as a backbencher.