London, Sep 24 - British Business Minister Shriti Vadera, one of Prime Minister Gordon Brown's most trusted colleagues, is to quit and work full-time for the G20 group of nations, Brown said Thursday.

'I came to her and said 'This is the job for you',' Brown said in New York.

'Her expertise in this area is such that there is no one better to do this job,' Brown added.

Vadera, an ex-banker, will co-ordinate the hand-over of the G20 presidency from Britain to South Korea. She will work unpaid and will continue to have a desk in the Cabinet Office.

Vadera will start work for South Korea in the middle of October and is taking her post at the request of President Lee Myung-Bak, the department of business said.

'Shriti has real passion for the G-20 and has done excellent work, so this is a logical move for her and us,' her boss, Business Secretary Peter Mandelson, said in a statement.

Her duties as a business minister will be taken over by Mervyn Davies, who already serves in the Department for Business, Innovation and Skills.