Labour has promised to reform the planning process after a landslide election victory today.

It comes after fewer planning applications were submitted to Cornwall council last year than in any over the last decade.

Labour said it will build 1.5 million new homes over the next parliament by "bulldozing" restrictive planning rules, encouraging councils to build on brownfield sites, and identifying lower quality areas in the green belt for development, termed "grey belt".

Department for Levelling Up, Housing and Communities figures show Cornwall council decided on 5,397 planning applications in the year to March – down from 6,559 the year before, and the lowest figure of any year over the last decade.

Of these, 4,936 (91%) were granted, while 461 were refused. It meant the number of granted applications was also a decade-low.

Across England, councils decided 333,000 planning applications, 12% down on the previous year and the lowest recorded figure in the last decade.

Of these, 285,000 (86%) were granted, meaning both the proportion and total number of accepted applications slumped to a decade-low level.

Speaking to ITV News, Sir Keir Starmer said his first action as Prime Minister will be to reform the planning system.

He added: "We cannot go on with the system as it is. Infrastructure takes years. Housing takes years to build. We’re too slow. We’re too expensive. We’re over budget.

"We cannot go on like that. We have to take the tough decisions to get the country moving."

Shadow chancellor Rachel Reeves said the current system is a "barrier to growth", and Labour will "put planning reform at the very centre of our economic and political argument".

There was a particular focus on housing developments in Labour's manifesto. It said it would immediately update the National Planning Policy Framework "to undo damaging Conservative changes, including restoring mandatory housing targets".

But across the country, the number of granted planning applications for major residential developments – those which provide at least 10 residential dwellings – has fallen steadily over the last decade.

Last year, granted applications fell by 12%, slumping to the lowest level in a decade. In Cornwall, just 52 were granted last year, also a decade-low.

To boost housing development, Labour said it will support local authorities by funding additional planning officers, and "will not be afraid to make full use of intervention powers to build the houses we need".

However, it also pledged to ensure local communities continue to shape house building in their area.

Their manifesto said a "brownfield first" approach would be implemented, but admitted brownfield development is insufficient to meet housing needs.

Mark Booth, co-founder of house builder Hayfield, said "tweaking the current system isn’t enough". He added: "We need to find a solution that incentivises local planning authorities to deliver housing in all areas of the country."

Lizzy Galbraith, a political economist at abrdn, said housing targets such as those set out by Labour "are very ambitious – even with planning reform".