Barack Obama does stand-up comedy for a night

US president Barack Obama put aside policy pronouncements for a night and took a stab at stand-up comedy on Saturday at the annual White House Correspondents' Association dinner.

The dinner, one of the top yearly social events in Washington, drew leading Hollywood celebrities and some of America's most powerful politicians.

Obama competed for laughs with US late-night TV comedian Jay Leno, who told jokes at the dinner. Other celebrities at the event included film director Steven Spielberg, actors Morgan Freeman and Alec Baldwin and singer Jessica Simpson.

Obama ribbed among others vice-president Joe Biden, unsuccessful 2008 Republican presidential candidate John McCain and Goldman Sachs Group Inc, the Wall Street giant accused by US securities regulators of misleading investors.

Obama said he had not been sure he should attend the dinner, but Biden talked him into it.

"He leaned over and he said, 'Mr president, this is no ordinary dinner. This is a big ... meal.'"  As Obama delivered the line, he was interrupted by an extended electronic bleep of the type used to block profanity on US air waves.

The zinger recalled Biden being caught on microphone congratulating Obama in March for a "big (expletive) deal" on his victory in the US healthcare overhaul fight.

Obama noted that McCain, now up for re-election as a Republican senator from Arizona, recently had said he had never identified himself as a maverick.

"And we all know what happens in Arizona when you don't have ID," the president said. "Adios Amigos."

It was a jibe reflecting concerns among many Hispanics that they may be unfairly singled out under a new state law in Arizona cracking down on illegal immigrants.

Obama said all of his jokes at the black-tie dinner were "brought to you by" Goldman Sachs, the investment bank charged two weeks ago with fraud by the US Securities and Exchange Commission.

Don't worry, he told the nearly 3,000 people in attendance. "They make money whether you laugh or not."