SIR Howard Davies has joined the board of Royal Bank of Scotland (RBS) with immediate effect, the state-owned lender has confirmed.

The economist had been due to join RBS as a non-executive director after the bank's annual general meeting on June 23.

But the appointment was delayed until the final report of the UK Airports Commission chaired by Sir Howard was published.

Sir Howard will succeed Sir Philip Hampton as chairman of the state-backed lender on September 1.

The bank said in a statement: "The Royal Bank of Scotland Group plc announces today that, further to its announcement on 22 June 2015, Sir Howard Davies will join the Board as a Non-executive Director with immediate effect. He will assume the role of Chairman on 1 September 2015."

Sir Howard's appointment as the next RBS chairman was confirmed by the bank on February 26.

He was presented as the bank as having an "extraordinary breadth" of experience across the financial services sector, having previously been chairman of the Financial Services Authority, deputy governor of the Bank of England, director general of the Confederation of British Industry and CEO of the Audit Commission.

He will continue to serve as a non-executive director of Prudential and professor of practice at Sciences Po, Paris alongside his role at RBS.

Sir Howard's arrival on the board comes after the UK Government said last week that it hopes to raise at least £25 billion by selling three-quarters of its stake in RBS.

It wants to offload £2bn in the current fiscal year with between £5.8bn and £6bn in each of the following years by the end of the decade.