LONDON (AP) — U.K. Treasury chief Philip Hammond has warned the two contenders to become the next prime minister that their expensive spending promises will be impossible to deliver if Britain leaves the European Union without a divorce deal.

Hammond said Monday that unless there is an orderly Brexit, the government's "fiscal firepower . will all be needed to plug the hole a no-deal Brexit will make in the public finances."

Foreign Secretary Jeremy Hunt and his predecessor in that job, Boris Johnson, are competing for the votes of about 160,000 Conservative Party members, who will choose the party's next leader.

Both are wooing members of the largely pro-Brexit Tory grassroots by promising to take Britain out of the EU, without a withdrawal agreement if necessary, while also cutting taxes and boosting spending.

Follow AP's full coverage of Brexit and the Conservative Party leadership race at: https://www.apnews.com/Brexit