Barack Obama is enjoying about a two-thirds approval rating for his first days as the US President, a poll released on Sunday found.

The Gallup Organisation survey found 68 per cent of Americans approve of Obama's performance as the nation's chief executive.

That's a number near the high end for new presidents, but short of President John F Kennedy's 72 per cent in 1961.

The poll also found that 12 per cent in the survey disapprove of Obama's job performance, a typical number all presidents face after an election.

Among presidents elected to their first term, Kennedy had the highest initial job approval rating, that of 72 per cent, in Gallup polling three weeks after his inauguration. Next were Dwight Eisenhower with 68 per cent approval and Jimmy Carter with 66 per cent. Every other president elected to a first term since Eisenhower started office with at least majority job approval -- Richard Nixon's 59 per cent; Ronald Reagan's and George H W Bush's 51 per cent; Bill Clinton's 58 per cent and George W Bush's 57 per cent.

Compared with his immediate predecessors, Obama faces fewer Americans who disapprove of his performance. Clinton faced 20 per cent disapproval after taking office in 1993, and George W Bush faced 25 per cent disapproval after the Supreme Court delivered him the presidency in 2000 after the controversial Florida recount.

Gallup finds approval ratings improved after about 100 days in office for all recent elected presidents, except Carter and Clinton, as Americans became more familiar with their work.