Malcolm Turnbull, Julie Bishop and Scott Morrison — the three Liberal ministers seen as leadership candidates in February's failed spill motion — are all set to campaign in the Canning byelection over the next 10 days.

But Prime Minister Tony Abbott, who is in Northern Australia for the rest of this week, would not say on Tuesday if he would make another appearance with Liberal candidate Andrew Hastie ahead of the crunch by-election contest because "life is pretty busy".

Tony Abbott with Liberal MP Andrew Hastie in 2015. Credit:Thomas Davidson

In addition to Mr Turnbull, Ms Bishop and Mr Morrison, Treasurer Joe Hockey and Finance Minister Mathias Cormann plan to campaign in the seat over the next week.

The Canning byelection is due to be held on September 19, but with Parliament to sit for two weeks from September 7, next week offers the most straightforward opportunity for senior ministers to participate in the campaign.