A council could secure vital funding by joining the West of England Combined Authority (Weca), its leader has said.
The combined authority currently represents three of the four councils in the greater Bristol area.
North Somerset Council leader Don Davies said it was "stupid" not to join the partnership when it formed in 2016.
But joining now could see the council access additional funding to help retrain people who have lost jobs during the pandemic, Mr Davies added.
Weca is made up of three of the councils in the region - Bath and North East Somerset, Bristol City and South Gloucestershire.
The Local Democracy Reporting Service (LDRS) said local government minister Luke Hall has written to metro mayor Tim Bowles and councillors in the four local authorities, saying the "potential for an expanded Weca" could "substantially benefit the people and businesses there".
"Expansion would enable key economic levers all being exercised over the same geography by a strong and accountable mayor and combined authority," he added.
North Somerset Council joining Weca could potentially see up to £900m of additional funding brought to the greater Bristol area, according to the LDRS.
Mr Davies said the councils and Weca would all have to agree to its membership bid, adding: "I'd imagine there would be some additional funding, of the type Weca already gets.
"The other thing that is even more important with the Covid situation is funding for adults skills.
"There's going to be a lot of people losing their jobs and needing training. That will make a massive difference."
Legislation would need to be in place by late March 2021, before the local elections are called.