London’s mayor is currently enrolled in a pension scheme where City Hall pays £20,400 in employer contributions this financial year and Sir Sadiq pays £19,400.

According to the Evening Standard, the LGPS is viewed as “gold-plated” as it guarantees an income protected from inflation.

Access to the scheme was denied to councillors and mayors in 2014 under the coalition government. The Government plans to restore the scheme to those elected officials as part of wider local government reforms.

Communities Secretary Steve Reed announced the move during a speech to councillors at Labour’s party conference in September.

Mr Reed said he was “outraged” when the Conservative government barred councillors from accessing pensions through the LGPS.

He told conference delegates at a fringe event in Liverpool: “I am proud as can be to announce today the reversal of that decision – you deserve it.”

A year of contributions under Sir Sadiq’s existing arrangement would provide an inflation-linked retirement income of about £2,500.

But under the proposed LGPS expansion, the same period would generate an annual income of £3,475.

The Local Government Association welcomed the move after it was announced. A spokesperson for the association said councillors work very hard to represent their communities and sacrifice working hours and family time to carry out their roles.

They argued that “fair” remuneration, including pension provision, was vital so people from all walks of life feel able to stand for public office.

The spokesperson concluded: “Reinstating councillors’ access to the Local Government Pension Scheme is an essential step in recognising their dedication and service to their communities.”