Coalition likely to lose WA seats: Barnett

It's unlikely the coalition will retain all of its lower house seats in Western Australia, Premier Colin Barnett says.

Just as Prime Minister Malcolm Turnbull was on his way to Government House to ask the governor-general to dissolve both houses of parliament and call a July 2 federal election, Mr Barnett predicted the result will be "close".

"I think Malcolm Turnbull will win, but I don't presume that for a moment," Mr Barnett told reporters in Perth on Sunday.

He said it would be a "tough ask" for the coalition to keep all 12 of its WA seats in the House of Representatives, but it would maintain a "strong majority".

WA has 15 lower house seats, rising to 16 with the creation of the division of Burt in Perth's southeast.