LONDON, July 16, 2022 (BSS/AFP) - The five remaining Conservative candidates to become Britain's next prime minister clashed Friday night over tax and honesty in politics in their first TV debate, as they fight to make an eventual two-person run-off.

The 90-minute debate -- the first chance in the days-old contest for both the frontrunners and lesser-known contenders to pitch their credentials to a national television audience -- saw relatively few direct confrontations between them.

But when they did erupt, it came largely over taxation, with former finance minister Rishi Sunak, one of the frontrunners, forced to defend plans to keep rates at some of the highest levels in decades.

Sunak, who has topped the first two rounds of voting by Tory MPs this week as the race narrows towards a final pair next week, is up against several contenders vowing to cut various taxes immediately.

The wealthy and polished media performer, whose political fortunes have been damaged by his family's own tax affairs, urged both caution and patience as the UK grapples with the worst inflation in 40 years.

"Borrowing your way out of inflation isn't a plan, it's a fairytale," Sunak told Foreign Secretary Liz Truss, as she touted her tax-slashing plans in the face of a spiralling cost-of-living crisis.

Truss -- battling to unite the ruling party's right wing behind her so-far lagging campaign after twice finishing third in votes -- has positioned herself as a low-tax free marketeer.

She has backing from prominent Johnson loyalists, despite wanting to reverse his government's recent tax rise earmarked for healthcare.

"You cannot tax your way to growth," Truss said. "I think it is wrong to put taxes up."

- Tugendhat tops poll -

Johnson last week announced his resignation as Tory leader after a cabinet insurrection led partly by Sunak, following months of controversies.

The five Conservative MPs bidding to succeed him initially faced hostile questions, from an invited audience of voters and a single political anchor, over trust and integrity.

That allowed long-shot candidates Tom Tugendhat, a prominent backbencher, and former equalities minister Kemi Badenoch, to pitch themselves as untainted and ready to provide a fresh start.

"Are you serving the people of the United Kingdom or are you serving your career? Because that's the real question tonight," Tugendhat said, repeatedly drawing applause from attendees.

A snap poll of 1,159 viewing voters by Opinium found 36 percent thought the former army officer performed best, followed by a quarter citing Sunak.

Just six percent said Truss, while Penny Mordaunt and Badenoch fared slightly better on 12 percent each.

In a sign of the shadow cast by Johnson, the contenders were asked if he was honest and none gave a wholehearted endorsement.

Tugendhat shook his head, Badenoch said "sometimes" while the other trio of former cabinet colleagues equivocated.

Mordaunt, who has emerged as the surprise bookmakers' favourite with strong grassroots' support, appeared uneasy directly criticising the party's outgoing leader.

"There have been some really severe issues and I think he has paid a price for that," she said.

The Royal Navy reservist -- briefly Britain's first woman defence secretary but demoted to junior minister roles under Johnson -- has been increasingly attacked by rival camps.

The claims include that she is inexperienced, incompetent in government jobs and has shifting stances on transgender rights.

"I take it as a big fat compliment that no one wants to run against me," Mordaunt said of the attacks.

- 'Knife fight' -

The ballots of Conservative MPs will end Wednesday, with the party's rank-and-file members then choosing from the two finalists following nationwide campaigning and hustings.

The winner will be announced on September 5.

While Johnson has said he will stay above the fray, his supporters have spoken acidly against Sunak, as the contest gets increasingly divisive.

The worsening acrimony prompted Tugendhat to call it "a knife fight in a phone box" ahead of the debate and urging the party to unite.

But some former cabinet members have also turned their fire on Mordaunt.

Attorney General Suella Braverman, who was eliminated Thursday, accused Mordaunt of failing to "stand up for women" as she backed Truss.

Meanwhile ex-Brexit minister David Frost alleged Mordaunt was "absent on parade" when they worked together on negotiations with Brussels.

Earlier Friday, the candidates took part in an online hustings, detailing policy priorities alongside warm words for the Tory base.

They will participate in another televised debate Sunday, before Tory MPs next vote Monday, when the field will likely be cut to four.

A further vote and TV debate is scheduled for Tuesday, before Conservative lawmakers decide the final pair of contenders Wednesday.