LONDON - The race to replace ousted British Prime Minister Boris Johnson heated up on Tuesday, with four contenders offering more policies to try to climb to the top two in a leadership contest that is splitting the governing Conservative Party.

Since Johnson said he would resign earlier this month after his scandal-ridden administration lost the support of many Conservatives, the remaining candidates have turned their fire on frontrunner, former finance minister Rishi Sunak.

Four candidates remain, with one to be axed after a vote of Conservative Party lawmakers later on Tuesday. Sunak's allies say his lead all but assures him of a place in the top two who will then court the party's membership to be appointed the next prime minister in September.

But foreign secretary Liz Truss is closing the gap with second-placed Penny Mordaunt, a junior trade minister, and the rankings can change as Conservative lawmakers whose preferred candidates have been ousted decide where to place their votes.

Both Sunak, Truss and Mordaunt presented policy offerings to try to add momentum to their campaigns, trying to move the focus away from pledges on tax cuts, at a time when Britain's flagging economy has left people with the tightest squeeze on their finances for decades.

Sunak, whose resignation as finance minister helped trigger Johnson's downfall, said he would implement harsher sentences for criminals who fail to attend court and would crackdown on grooming gangs if he became prime minister.

"It will be my top priority in government to keep the British public safe - and I will do whatever it takes to make that happen," he said in a statement.

NEW POLICY STATEMENTS

All four remaining contenders are keen to buttress some of their right-wing credentials to appeal to a party membership, which, according to 2020 research by Queen Mary University of London and Sussex University Party Members Project, tend to be older, male, southern English supporters of Brexit.

Truss, who has been a vocal supporter of Ukraine after Russia's invasion, repeated her commitment to increase defence spending up to 3% of gross domestic product by 2030.

"We live in an increasingly dangerous world where the threat level is higher than a decade ago, and we need a stronger deterrent to face down those threats and ensure Britain leads on the global stage," she said.

"My number one priority is keeping this country safe and people can trust me to do that."

Mordaunt also committed to Johnson's so-called levelling up agenda, or tackling regional inequalities in Britain.

"My economic plan will boost competition and growth up and down the country, creating the jobs of the future and enabling the country to live well," she said in a statement.

The four candidates, which include former equalities minister Kemi Badenoch in fourth place, will hope to gain more votes at Tuesday's ballot of the Conservative Party's lawmakers. The result will be announced at 1400 GMT.

One lawmaker who will not be able to vote is Johnson critic Tobias Ellwood, who lost the so-called whip - essentially being kicked out of the parliamentary party - for "his failure to vote in support of the government in the confidence vote last night", a spokesperson for the whips, or party enforcers, office said.

He had previously backed Mordaunt.

The three who go through will face another vote on Wednesday when the final two are expected to be announced. They will then have hustings to win over the party's 200,000 members, who will appoint Britain's fourth new prime minister in six years.

Badenoch, who some lawmakers have called on to stand down to speed up the race, voiced confidence she could move up the rankings.

"I do feel confident. There's everything to play for," she told Sky News. "My colleagues are looking at who's going to be winning the next election and I think I'm that candidate so let's see what happens."

(Reporting by Elizabeth Piper; Editing by Frank Jack Daniel and Angus MacSwan)