Jeremy Hunt, the underdog in a bitter battle with Boris Johnson to become Britain's next prime minister, on Monday called on his rival not to be "a coward" trying to

"avoid scrutiny" -- over both a domestic row and his policy agenda.

Foreign minister Hunt urged Johnson, who has become embroiled in a scandal over a dispute with his girlfriend that led to a police visit last week, to "man up" and show he can cope with questioning.

Johnson, the overwhelming favourite to replace Theresa May as Conservative Party leader, and therefore prime minister, has refused to discuss the early Friday incident.

He has also kept an unusually low profile during the weeks-old race, skipping a candidates' TV debate and doing barely any media interviews.

"I am not interested in debating Boris's private life," Hunt said in an article in The Times, arguing he instead wants to quiz Johnson on his Brexit plans and other ideas.

"A new prime minister needs the legitimacy of having made his arguments publicly and having them subjected to scrutiny.

"Only then can you walk through the front door of No 10 with your head held high instead of slinking through the back door, which is what Boris appears to want."

Urging Johnson to attend a TV debate proposed for Tuesday evening, Hunt added: "Don't be a coward Boris, man up and show the nation you can cope with the intense scrutiny the most difficult job in the country will involve."

Sky News said Monday that Johnson had so far declined its invitation to take part in the head-to-head debate, and that without him it would not go ahead.

"But we will reissue our invitation for Mr Hunt and Mr Johnson to debate live on Sky News next Monday, 1 July," the broadcaster added in a statement.

Johnson, 55, a former London mayor and foreign secretary, was involved in a loud altercation early Friday at the home of his 31-year-old girlfriend Carrie Symonds.

Neighbours called police after hearing screams, shouts and bangs at the south London property, shortly after Johnson had secured his place in the final run-off to become prime minister.

The couple, who were spoken to by officers but face no further action, have reportedly fled the home following the incident and a handful of anti-Johnson protesters gathering there Sunday.

When asked about it at a Conservative grassroots event Saturday, Johnson said: "I don't think people want to hear about that kind of thing." afp