LONDON - Britain's next prime minister Liz Truss has the right plan to tackle regional inequality, address rising costs of living and unite the ruling Conservative Party, outgoing leader Boris Johnson said on Twitter.

"Congratulations to @trussliz on her decisive win," Johnson said.

"I know she has the right plan to tackle the cost of living crisis, unite our party and continue the great work of uniting and levelling up our country. Now is the time for all Conservatives to get behind her 100 per cent."

(Reporting by William James; Editing by Kate Holton)