The latest stumbling block surrounds Britain’s bid to host the 2029 World Athletics Championships at London Stadium – because the event would clash with West Ham’s football fixtures.

British 800m star Keely Hodgkinson weighed in earlier this year, calling for a solution to be found; it is understood talks are ongoing.

Then there are the complex agreements drawn up after the 2012 Games.

UKA is understood to pay £35,000 a year under its 50-year lease to London Stadium, while West Ham’s Premier League relegation means the club’s £4.4m annual rent for the venue is halving, with taxpayers picking up the rest.

It costs £3m each time the London Stadium moves seats from a football set-up to an athletics configuration, but neither UKA nor Diamond League ticket-holders pay for it – the stadium does.

It brings the taxpayer’s total bill for using London Stadium in the year 2026-27 to £23m, as set out in the Greater London Authority budget.

A spokesperson for Sir Sadiq told the BBC the West Ham lease was “a bad financial deal for Londoners” signed under the previous mayor, with no break clause and “significant losses to the taxpayer”.

Sir Sadiq’s office praised the stadium as a “highly valued asset for London”, while at the same time he said he was “proud” of the Crystal Palace redevelopment and “continues to work with partners and the local community on plans for the major refurbishment of the athletics stadium”.

A senior athletics source said any “speculation regarding other venues is irrelevant” and London Stadium “continues to be an excellent venue” for the sport – but that bosses support investment in athletics facilities across the country, too.

The argument from Crystal Palace campaigners is that by investing in a ready-made stadium, taxpayers save money in the long run, and athletics has a natural home. They say concerts, offices and film shoots would bring a viable revenue stream.