The prime minister, Anthony Albanese, is expected to call the federal election on Friday for a polling day in early May, according to Labor sources.

Speculation had been rife in Canberra that Albanese could visit the governor general on either Friday or Sunday to capitalise on momentum from Tuesday’s federal budget and draw attention away from Peter Dutton’s budget reply speech on Thursday night.

Several senior Labor sources told Guardian Australia on Thursday afternoon they expected the election to be called on Friday, while other sources did not downplay that speculation.

The timing would draw attention away from Dutton’s budget reply speech, where the opposition leader will further detail his alternative vision for the country.

After opposing Labor’s surprise new income tax cuts, Dutton will use the major speech on Thursday night to commit to halving the fuel excise for 12 months while announcements on gas supply, housing and migration are also expected.

Albanese could seek to call an election for either 3, 10 or 17 May – with the earliest date the more widely anticipated. The prime minister said on Thursday morning “it’ll be called pretty imminently”.

“I can confirm that I’m not calling it today, but I will call it soon,” he told Triple M radio.

Labor MPs and strategists believe the government has wrestled back momentum over the past month after several big-ticket announcements – including an $8.5bn boost to Medicare – and intensifying scrutiny on Dutton and his policies.

The Coalition’s mixed messaging on breaking up insurance companies, Dutton’s dash to a Sydney fundraiser as his home state of Queensland braced for Cyclone Alfred and the idea of a referendum on deporting dual citizens prompted negative headlines and fuelled internal unease about the opposition’s strategy.

The opinion polls continue to point to a hung parliament after the election, forcing Albanese or Dutton to negotiate with the crossbench to form a minority government.

“He [Dutton] has made a series of unforced errors and we’ve been talking about the things we want to talk about,” one Labor minister said.

The growing expectation came as the Department of Prime Minister and Cabinet briefly published, then quickly deleted, a post on X stating that the government was “now operating in accordance with caretaker conventions, pending the outcome of the 2025 federal election”.

The government enters caretaker mode after parliament is dissolved, which has not yet happened.

Guardian Australia was told the post was published mistakenly and deleted shortly after it went live.