The BBC's Kim Ghattas in Washington says Mr Panetta's remark is the first time a senior American official has publicly taken this position.

BBC: Panetta backs Syria rebels arms plan

Kim Ghattas: I've flown to Seoul ahead of Hillary Clinton to get a sense of what South Korea is expecting from the new US administration.

BBC: Obama diary: Days 31-40

Trust may not be enough between the US and Russia, said top State Department official Ellen Tauscher in an interview with BBC state department correspondent Kim Ghattas.

BBC: Obama: Start nuclear treaty vital for national security

Kim Ghattas : He speaks Polish, he's been ambassador to South Korea, helped negotiate an end to the Balkans conflict and shuttled from Washington to Pyong Yang for three years, working on a denuclearisation deal with North Korea.

BBC: Obama diary: Days 61-70

While the Saudi minister did not detail his vision of a quick solution in public, it is likely that options were discussed behind closed doors in the meeting between Mrs Clinton and King Abdullah, says the BBC's Kim Ghattas, who is travelling with the top US diplomat.

BBC: Saudi FM al-Faisal doubts Iran sanctions plans