Outgoing British Prime Minister Boris Johnson speaks outside Downing Street in London, Tuesday, Sept. 6, 2022. [AP]

LONDON (AP) - Prime Minister Boris Johnson left his Downing Street office for the last time on Tuesday, August 6 before heading to Scotland to formally offer his resignation to Queen Elizabeth II.

The British leader, who announced his intention to step down two months ago, is expected to meet with the Queen in the late morning at her Balmoral estate to begin the transfer of power to Liz Truss.

Truss, who was named leader of the ruling Conservative party on Monday, August 5 will be appointed prime minister during her own audience with the queen a short time later.

Speaking outside No. 10 Downing Street, Johnson said his policies had given the country the economic strength to help people weather the energy crisis before he signed off his typical bluster.

"I am like one of those booster rockets that has fulfilled its function," Johnson said before getting into a car and leaving the gates of Downing Street for the last time as prime minister.. "I will now be gently re-entering the atmosphere and splashing down invisibly in some remote and obscure corner of the Pacific.''

This is the first time the handover of power is taking place at Balmoral, the monarch's summer retreat in Aberdeenshire, rather than at Buckingham Palace in London. The ceremony was moved to Scotland to provide certainty about the schedule because the 96-year-old queen has experienced problems getting around that have forced palace officials to make decisions about her travel on a day-to-day basis.

Truss, 47, takes office a day after the Conservative Party's 172,000 members elected her to lead their party.