(Bloomberg) -- Keir Starmer said his Labour Party is preparing for a UK general election as soon as May 2024, warning that Prime Minister Rishi Sunak’s Conservatives would fight dirty to try and stay in power.

Sunak has to call a national vote by January 2025, and Tory officials have repeatedly said the premier is likely to wait until the autumn to allow as much time as possible for the economy to recover.

Read more: Keir Starmer Battles Dire State of UK in Bid to Emulate Blair

But speaking at a business forum at Labour’s annual conference in Liverpool, northwest England on Monday, Starmer told delegates Sunak could spring a surprise by going to the polls in the spring. “It’ll either be May or October,” he said. “Our team is ready for May. Nobody would rule out May.”

Two Labour strategists said they think Sunak will try to coincide with the London mayoral election in early May, with incumbent Sadiq Khan’s popularity waning in polls. That’s in part because of Khan’s push to expand the capital’s low-emission zone, which the Tories see as helping them to narrowly hold off a Labour surge in a special election in northwest London this year. That would fit Sunak’s attempts to portray Labour as anti-motorist, the people said.

There are other potential advantages for Sunak to go earlier, according to Labour strategists. Local elections are also set for May and are typically unfavorable to the governing party, so Sunak could try to avoid seeing a potential wipe-out of Conservative councillors denting morale.

One Labour official also noted that a May election would mean voters cast their ballots before any uptick in asylum seekers across the English Channel from France, which usually happens in the summer months and which Sunak has pledged to stop. The other rationale is economic, given the earlier Sunak calls a vote, the fewer Britons will have had to re-mortgage at higher interest rates.

To be sure, it could also be in Labour’s interests to try to pressure the Tories into an early election. The opposition party could have the upper hand by restricting time for Sunak to whittle down Labour’s lead in the polls, which has been near 20 percentage points for months.

Read more: Sunak Starts Reset by Tearing Up Project Johnson Championed

Whenever it comes, Starmer said he’s expecting the Tories to “go low” in the campaign. “My worry is instead of making decisions in the long-term interests of the UK, the government is in danger of making short-term decisions” to try to create dividing lines, he said. “I’m predicting, I’m afraid, that the election campaign will descend into that place rather than where it should be.”

At the same event, hosted by Bloomberg, shadow business secretary Jonathan Reynolds said Labour would be unlikely to match any promises by the Conservatives to significantly cut taxes. Chancellor of the Exchequer Jeremy Hunt has said there is no fiscal headroom to do so, based on forecasts by the UK’s Office for Budget Responsibility, though that has not prevented calls from senior Tories to reduce the burden on struggling Britons before a vote.

“Have you heard anything from the OBR in the last few years?” Reynolds said when asked about the potential for tax cuts.

--With assistance from Emily Ashton.

©2023 Bloomberg L.P.