Speaking exclusively to Swindon24 following Wednesday’s Budget announcement, Councillor Sumner said Oxfordshire’s change of position came after it became clear that a devolution deal would only be offered if Swindon was included.
The Government has confirmed that the Thames Valley, covering Swindon, Berkshire and Oxfordshire, will progress towards creating a mayoral authority, potentially unlocking substantial investment in housing, infrastructure and economic growth.
However, the agreement appeared to collapse in June when Liberal Democrat leaders in Oxfordshire refused to support the proposals. Asked what had changed behind the scenes, Cllr Sumner suggested the Government’s position had been decisive.
“I think you’ll find that the government firmed up on the situation, and said that Thames Valley must include Swindon,” he said.
“There was a previous court case which said that the government can’t dictate mayoral areas, but the offer of the devolution deal was on the table if Swindon was included, and Oxfordshire suddenly decided that actually the benefits to them would be lost if they fought against that.”
Pressed on what ultimately persuaded Oxfordshire to reconsider, he suggested the financial consequences of missing out had become impossible to ignore.
“Lose the prospect of businesses and Oxfordshire County Council, the whole of Oxfordshire, losing this potential investment is unthinkable,” he said.
He also challenged suggestions that Swindon was not a suitable partner.
Their reason for not including Swindon, they didn’t think we were a perfect fit. Here we are lined up alongside Reading and Slough. We’re one of the three big beasts of the M4 corridor.”
Asked what the town had actually secured, he said the long-term opportunity could be worth tens, if not hundreds, of millions of pounds in support for housing and economic growth.
“This is a real opportunity to turbocharge our economy,” he said.
“Obviously, others within the new Thames Valley mayoral area will be pitching for the same. But actually, Swindon is shovel ready with town centre development sites.”
He believes Swindon’s existing development land could provide an alternative to building on greenfield sites elsewhere in the region. The Government’s announcement includes a proposed £9.1 million allocation from its Good Growth Funds to support priorities across the Thames Valley.
However, no specific allocation to Swindon has been confirmed, and the larger sums discussed by Cllr Sumner represent potential future investment rather than funding already secured.
Asked what difference the agreement could make to ordinary residents, Cllr Sumner highlighted improved infrastructure planning, more employers, additional jobs and apprenticeship opportunities.
He said the council was already investing more resources into attracting businesses to Swindon, which could increase business rates income.
“There will be funding which is specifically for mayoral areas, which will come from government as soon as next year,” he said.
“People can expect to see our economy grow; they can expect to see more businesses want to come to Swindon and more jobs.”
The proposed authority would oversee strategic issues including transport, skills, investment and affordable housing, while Swindon Borough Council would retain responsibility for everyday local services.
One challenge will be securing Swindon’s share of investment while competing with larger, wealthier neighbours. Cllr Sumner insisted the town’s lower costs and available workforce would make it an attractive destination for businesses.
“We’re a lot cheaper as a location than places like Reading or Slough, but we’ve got a workforce here, and we’ve got a willingness to grow and a willingness to welcome economic growth,” he said.
The new authority would be led by a directly elected mayor, raising questions about how funding decisions would be made. Cllr Sumner said the mayor would work alongside political leaders from across the Thames Valley.
“They will have to work with the mayor to ensure that the funding is spent according to the wishes of those within the devolution deal,” he explained.
The 13 councils involved are expected to consider proposals in December, ahead of a stakeholder consultation in early 2027. A formal submission to the Government is expected in spring 2027, subject to the necessary approvals.
Cllr Sumner anticipates a shadow mayoral authority being established during 2027, followed by elections for the Thames Valley’s first mayor in 2028. For Swindon, the announcement offers an opportunity to attract investment and influence major regional decisions.

















