Top Tories Liz Truss and Dominic Raab have both staked a claim for use of a 115-room country retreat in a post Cabinet reshuffle bust up.
Chevening, a 17th Century manor in Kent, has been used as a grace-and-favour residence by the Foreign Secretary since 1981.
Ms Truss is said to have put in a bid for its use since becoming Foreign Secretary in Boris Johnson's brutal Cabinet shake-up on Wednesday.
But she faces a rival claim from her predecessor Mr Raab, who was moved to the Ministry of Justice after his disastrous handling of the Afghanistan crisis.
Mr Raab was also given the title of Deputy Prime Minister - interpreted by some as a consolation prize for his demotion - which could allow him to keep using Chevening.
Downing Street said Boris Johnson had not made a decision over which of the squabbling Tories would get access to the country retreat.
Asked about the stand-off, the Prime Minister's official spokesman said: "You will appreciate that the reshuffle is still ongoing.
"There is a long process in place for nominating the occupants of Chevening House and we will update in due course."
But a source said Downing Street had already privately agreed that Mr Raab and Ms Truss will share Chevening.
It is understood that discussions are under way about how the arrangement will work in practice.
The lavish home is used by other groups and organisations, not just the minister who has responsibility for it.
Mr Johnson was forced to share Chevening when he was Foreign Secretary, splitting its use with Brexit Secretary David Davis and International Trade Secretary Liam Fox.
During the Coalition years, Foreign Secretary William Hague and Deputy PM Nick Clegg also shared access to the estate.
The grand 115-room manor near Sevenoaks stretches across 3,500 acres of parkland.
It was left to the nation in 1967 by the seventh Earl of Stanhope "on condition that it was occupied by either the Prime Minister of the day, a Cabinet Minister or a descendant of King George VI", according to the House of Commons Library.
The Prime Minister has his own grace-and-favour residence - Chequers, in Buckinghamshire
