The new Affordable Homes Programme will form the centrepiece of the Spending Review, delivering long-term certainty for developers and doubling current investment levels.

The new deal will average £3.9bn a year, up from just £2.3bn a year under the previous government’s five-year £11.5bn programme running from 2021 to 2026.

By the end of this Parliament, annual spend is set to hit £4bn in 2029/30, almost double the previous rate.

The ten-year funding deal offers long-term certainty to affordable homes the sector, where new build activity has slowed because of funding commitments to upgrade existing stock to meet stricter fire safety regimes.

Alongside the funding boost, Reeves will confirm a ten-year social rent settlement from 2026, allowing rents to rise at CPI+1% and helping housing providers borrow and invest more in new and existing stock.

The package comes as part of Labour’s wider “Plan for Change” and follows reforms to the planning system already forecast by the OBR to add £6.8bn to the economy and lift housebuilding to its highest level since the 1980s.

A government source said: “We’re turning the tide against the unacceptable housing crisis in this country with the biggest boost to social and affordable housing investment in a generation.”