Rishi Sunak has gained a valuable ally in his expected bid for No 10 as Boris Johnson backers were challenged over claims that he has reached the number required to secure a spot on the Tory ballot paper.

In a blow to Mr Johnson’s campaign should he seek a second stint in Downing Street, International Trade Secretary and former leadership contender Kemi Badenoch threw her weight behind the ex-chancellor, insisting now is not the time for “nostalgia for the cavalier elan of 2019”.

She admitted she had “on occasion” been a member of “the Boris Johnson fan club”, but she said the Tories are not “organising a popularity contest”, and stressed the party is “not a vehicle for any one individual’s personal ambitions”.

Mr Johnson has returned to the UK to plot a second run for the top job in a move that has divided opinion among Conservative MPs, including his former allies.

He arrived at Gatwick Airport on Saturday morning with his family after breaking off from a holiday in the Dominican Republic after Liz Truss’s dramatic resignation on Thursday.

He was rumoured to be planning talks with Mr Sunak on Saturday – possibly face to face – but reports suggested there had been a delay.

The BBC later said a meeting had taken place, but this has not been corroborated to the PA news agency by either camp.

Meanwhile, an ally of former home secretary Suella Braverman told PA that she had been personally “heavily courted” by both Mr Johnson and Mr Sunak and is likely to decide who to back for the Tory leadership on Sunday.

Sir James Duddridge, a Johnson ally, claimed the ex-Prime Minister had the backing of the 100 MPs required to make it on to Monday’s ballot.

Former minister Karl McCartney tweeted: “Very pleased (along with so many of my constituents who came over to chat to me earlier today all over the city) that @BorisJohnson has more than 100 backers/nominations, and therefore could be on the ballot on Monday.”

But Sunak supporter Richard Holden cast doubt on this suggestion, arguing that the 100 public declarations had not been announced “because they don’t exist”.

Sir Robert Syms, another Sunak backer, wrote on Twitter: “If Boris has 100 in the bag why is his campaign putting out pics of him begging for votes?”

Despite being the only candidate to declare so far, Cabinet minister Penny Mordaunt is lagging behind on public support from MPs, with just 21 to Mr Johnson’s 44 and Mr Sunak’s 113, according to a PA tally.

Setting out her plan to “unite the party and the country” in the Express, she warned the Tories had “let ourselves become distracted by internal disputes”.

Ms Mordaunt used her pitch to stress the need to “make Brexit work”, “focus on the potential of all our citizens” and “defend our Union and its territorial integrity”, pledging her support for reforming the controversial Northern Ireland Protocol.

She insisted she is not seeking the top job for an “easy ride”, and vowed to build a government which “draws from all our best talent”.

Writing in the Sunday Times, Ms Badenoch said her party must remind people that “Conservatives care about the country, not ourselves”.

The International Trade Secretary suggested Mr Sunak would bring a “disciplined approach” to Government, citing his “fiscal conservativism” and stressing that “right now, being able to say no is what we need”.

She said everyone in the party will need to make “sacrifices” to prove to people the Tories can “unite”.

For her, this means refraining from a second leadership bid, she said, while some will have to forsake a job in government under their preferred candidate “so that others can be brought into the tent”.

Mr Johnson’s potential return has divided opinion even among his allies in the parliamentary party, including his former deputy prime minister and foreign secretary Dominic Raab.

Mr Raab said “we cannot go backwards” and pointed out the ex-Prime Minister faces an investigation into his actions over partygate.

He backed Mr Sunak, saying he was “very confident” the former chancellor would stand.

Rishi Sunak outside his home in London on Saturday morning (Beresford Hodge/PA)
Rishi Sunak outside his home in London on Saturday morning (Beresford Hodge/PA)

Moments after Mr Johnson landed back in the UK, ex-home secretary Priti Patel said he had her support – but his potential bid suffered a setback as former close allies Steve Barclay and Lord Frost urged colleagues to back Mr Sunak.

Mr Johnson’s father Stanley predicted that his son would put his name forward and beat Mr Sunak in a head-to-head contest.

The former PM has so far won the support of six Cabinet ministers: Ben Wallace, Jacob Rees-Mogg, Simon Clarke, Chris Heaton-Harris, Alok Sharma and Anne-Marie Trevelyan.

But he was lagging behind in nominations, albeit ahead of Ms Mordaunt.

The Leader of the House, who finished third in the last leadership election, said she had been encouraged by the support she had received from fellow Conservative MPs and wanted to unite the party.

She also assured Jeremy Hunt he could stay on as Chancellor if she won.

Tory MPs will vote on Monday, and two candidates will be put forward to the party membership unless one pulls out, with a result being announced on Friday.

Candidates have until 2pm on Monday to secure the 100 nominations, limiting the ballot to a maximum of three candidates.

Supporters of Mr Johnson believe that if he can make it to the last two, he will win in the final online ballot of party activists with whom he remains hugely popular.

Some MPs have warned they would resign the Tory whip and sit in the Commons as independents if Mr Johnson returned to Downing Street.