Here are some of the potential contenders to be the new leader of the ruling Conservative Party.

STEVE BAKER

Prominent supporter of Brexit and former minister Steve Baker, a senior Tory backbencher, confirmed on Thursday he is seriously considering putting himself forward for the top job.

He told Times Radio that people are asking him to do it, and it would be "dismissive and disrespectful" if he did not heed expressions of support.

SUELLA BRAVERMAN

The Attorney-General launched an unlikely leadership bid as support for Johnson crumbled around him on Wednesday night.

Previously loyal to the departing prime minister, she told broadcaster ITV he had handled matters "appallingly" in recent days and "the balance has tipped now in favour of saying that the prime minister - it pains me to say it - but it's time to go".

Braverman, elected as an MP in 2015, is regarded as something of an outsider for the leadership given the party grandees already tipped to be in the running.

SIR ROBERT BUCKLAND

The new Secretary of State for Wales has declined to rule out running as Tory leader.

"I want to see the next prime minister as a person who embodies the values that I believe in," he told BBC radio on Thursday.

JEREMY HUNT

The former foreign secretary and ex-health secretary has been a persistent backbench critic of Johnson.

Hunt is widely expected to make a fresh bid for the leadership, having been runner-up to Johnson in 2019, and is among the early favourites with bookmakers.

SAJID JAVID

Alongside Rishi Sunak, Javid's resignation on Tuesday caused chaos in No.10, as the health secretary from famously humble beginnings left the government.

He further stuck the knife in with an emotional resignation speech in the House of Commons, while Johnson sat, stony-faced, on the front benches.

State school-educated Javid is the son of a bus driver who arrived in England from Pakistan in the 1960s.

He held ministerial roles in housing, business and culture before becoming chancellor, and then health secretary in the middle of the pandemic.

Javid made it to the final four in the contest to replace Theresa May as Conservative leader in 2019.

He told reporters after his resignation on Tuesday evening that he was looking forward to spending time with his family - but for how long?

PENNY MORDAUNT

Another front-runner with the bookies, Mordaunt made waves in 2019 as the UK's first female defence secretary before being fired by Johnson shortly after he became prime minister.

She played a prominent role in the Leave campaign in the 2016 Brexit referendum.

RISHI SUNAK

Perhaps the front-runner, the former chancellor's rise from relative obscurity to household name came as he turned on the spending taps to protect jobs through the furlough scheme when the coronavirus pandemic struck.

His calm and measured delivery during televised COVID-19 briefings, and his viral declaration of love for a popular soft drink, will have endeared him to those perhaps not always plugged in to the political goings-on, as well as his resignation on matters of principle on Tuesday.

His stock took a tumble more recently following disclosures his wife had non-domicile status for tax purposes, and criticism that he was too slow to respond to the cost-of-living crisis.

LIZ TRUSS

The Foreign Secretary has made little secret of her leadership ambitions, with a series of high-profile interventions and photo opportunities in which she appeared to be channelling late prime minister Margaret Thatcher.

Despite being a fervent Johnson loyalist, she was nowhere to be seen as the government crumbled around him.

Her hard line on Ukraine, insisting Russian forces must be driven from the country, and threats to tear up the Northern Ireland Protocol with the EU play well with sections of the party.

TOM TUGENDHAT

The chairman of the Foreign Affairs Committee became the first to announce his intention to stand for leader should Johnson be turfed out - with his declaration made in January.

He repeated his position in Friday's Daily Telegraph, saying he was putting together a "broad coalition" offering a "clean start".

The former soldier wrote in the paper: "I have served before - in the military, and now in Parliament. Now I hope to answer the call once again as prime minister".

BEN WALLACE

The defence secretary has won admirers in Westminster for his straight-talking and straightforward approach, particularly among Tory MPs who pressed for the UK to increase its defence spending, although cuts to the size of the army remain a cause for concern.

Wallace, who served in the Scots Guards, remains a key voice in the UK's response to Russia's invasion of Ukraine and this increased exposure could assist any leadership bid.

NADHIM ZAHAWI

The former education secretary is regarded by some as a "safe pair of hands" if other candidates prove too divisive.

Iraqi-born Zahawi was a successful businessman and came to wider prominence as vaccines minister during the pandemic where he was credited with playing a key part in the successful rollout of the jab.

Australian Associated Press