Western Australia’s opposition leader is promising to crack down on interstate companies winning government contracts if the Liberals are elected at next year’s election.

Liza Harvey has pledged that within 100 days of coming to office, she will rewrite the McGowan government’s WA Jobs Act which preferences local suppliers but stretches the definition to include those from the eastern states and even New Zealand.

Under the proposed $50 million local jobs guarantee, suppliers will only be defined as local if they are within 125 kilometres of a project.

Such businesses will be given preferential treatment on all state government contracts through a local benefits test, and contracts will only be awarded interstate or internationally when specific services are unavailable.

It is Ms Harvey’s first major promise ahead of the election next March.

“The COVID crisis has hurt struggling households and small businesses,” Ms Harvey said on Monday.

“The world has changed and our economy has been impacted and only the Liberals will put local jobs first.”

Government agencies will also be forced to reveal in their annual reports why they chose interstate or overseas suppliers for any contracts.

The plan will be overseen by a local jobs commissioner who will report directly to the premier.

Ms Harvey outlined almost $9 million worth of contracts she said had recently gone to eastern states companies, describing the existing local jobs act as a “terrible policy”.

The McGowan government estimated local workers had filled almost 13,000 jobs in the first year of the legislation.

Recent opinion polls have shown high levels of approval for Premier Mark McGowan and his government, who came to power in 2017 with a landslide victory.

The premier on Monday visited the state’s far north, announcing the selection of lead contractor Georgiou Group for Broome’s Chinatown stage two revitalisation project.

The contractor is targeting 70 per cent local content with work expected to commence in November.

“This is all about jobs for the Kimberley … making it even more attractive for West Australian tourists to holiday here and spend their money in Western Australia,” Mr McGowan said.

No new cases were reported on Monday. Three remain active.