The HM Treasury Budget document, published yesterday afternoon, said that ministers would "develop, with local partners, a long-term spatial framework to support strategic planning in the OxCam Arc", the corridor of land to the north of London connecting Oxford, Milton Keynes, Bedford and Cambridge.
"This will support the area’s future economic success and the delivery of the new homes required by this growth up to 2050 and beyond," it added.
Development of a spatial vision was one of nine recommendations made by the government's infrastructure advisor the National Infrastructure Commission (NIC) in a 2017 report which first set out a blueprint for the growth arc.
The NIC report also called for one million homes to be built in the growth corridor by the middle of the century "if the arc is to achieve its economic potential".
The government backed the NIC vision in the 2017 Autumn Budget and announced a commitment to build one million homes in the arc.
Then in the 2018 Budget statement, it said it would "explore options" for production of a spatial vision and said a "joint vision statement" would be published in the spring of 2019 as a "first step".
However, ministers confirmed in March 2019 that a decision on whether to develop a "spatial vision" for the Oxford to Cambridge growth arc had still not been made.
Just a few days earlier, the NIC warned that failure to produce a spatial vision could compromise the success of the project.
In addition, yesterday's Budget document said the government "is also going to examine and develop the case for up to four new development corporations in the OxCam Arc at Bedford, St Neots/Sandy, Cambourne and Cambridge, which includes plans to explore the case for a New Town at Cambridge, to accelerate new housing and infrastructure development".
In July 2018, former housing minister Kit Malthouse wrote to local authorities in the arc to invite them to submit "ambitious proposals" for new settlements as part of the government's plans to increase housing delivery in the area.
In October 2018, he revealed that the government had received about 14 responses. Among them was plans to expand Milton Keynes to become a city.
A total of 26 authorities make up the corridor, which covers Oxfordshire, Cambridgeshire, Peterborough, Milton Keynes, Buckinghamshire, Bedfordshire and Northamptonshire.
The four development corporation locations are all between Bedford and Cambridge along the proposed central section of the new East West Rail line, which would connect Oxford and Cambridge. Earlier this year, the government announced its preferred route for the line's central section.
Yesterday's Budget document went on to say that ministers would "subject to planning consents, build a new rail station at Cambridge South, improving connectivity to the world-leading research facilities of the Cambridge Biomedical Campus – the largest cluster of medical and life sciences research in Europe".
Elsewhere, in the Department for Transport's new Roads Investment Strategy, it was revealed that ministers are "pausing" plans for the new Oxford-Cambridge expressway.