Sydney: Malcolm Turnbull has committed to run as prime minister in a 2019 election, two days after he said he would leave parliament if he lost the prime ministership.

“I can assure you I will be prime minister for a very long time,” Turnbull told reporters on Monday.

“I will be running at the 2019 election and will win. So that’s my commitment.”

Turnbull refused to enter into the bitter internal feud, fuelled by Tony Abbott, that continues to plague the government, but the industry minister, Arthur Sinodinos, has warned that if Turnbull left parliament, the battle for his seat of Wentworth would be tough.

On Sunday Turnbull said he would leave parliamen t if he lost the prime ministership. His comments again raise the potential of a by-election for the Coalition government, which holds a one-seat majority in the lower house.

Sinodinos, a key Turnbull ally and former treasurer of the New South Wales Liberal division, said Wentworth, a small-l liberal stronghold in the eastern suburbs of Sydney, proved the Liberal party had to cater for both liberal and conservative views.

“Wentworth is always a tough seat to win and Wentworth is a good illustration of the challenge the Liberal party faces, that it has to be a party for all parts of Australia, it has to be a party that appeals to philosophies across Australia and that is why I say it is an amalgam of liberal and conservative,” Sinodinos said.

Sinodinos said John Howard realised the need for a pragmatic principled leader who combined the best of conservative and moderate traditions “while indicating to the community we are not just there to shove one particular view of the world down their necks”.

Sinodinos was speaking as Abbott continued his campaign of destabilisation, which in the past week has included laying out an alternative policy manifesto, calling for the examination of nuclear subs which he did not do as leader and calling for a change of rules in the NSW Liberal division, which he also failed to move on when it was called for three years ago.

Adding fuel to the Abbott campaign were remarks by Christopher Pyne a week ago, claiming victory for the moderates in the Liberal party to a meeting of factional allies and hinting at a plan to get marriage equality passed.

Barnaby Joyce described the internal divisions of his Coalition partner, the Liberal party, as an “accursed soap opera” full of “fluff and mirrors”.

Joyce backed in Turnbull’s leadership and accused critics of having an awful lot of spare time.

“If other people want to have other peripheral discussions about basically fluff and mirrors, well they can do it but I’m not going down that path, that’s not what I get paid my wage for,” Joyce told the ABC.

“I want my nation, your nation, your listeners’ nation to be a stronger place and that’s what I get paid my dollars by your listeners to do and I’m not going to get involved in this accursed soap opera and if other people want to get involved with that, go right ahead.”

At the same time, the acting Labor leader, Tanya Plibersek, has reflected on her party’s bitter internal division during the Rudd-Gillard-Rudd governments, saying she feels bad for the country.

— Guardian News & Media Ltd