WASHINGTON (AFP/REUTERS) - United States President Barack Obama cracked jokes and poked fun at rivals on Saturday (April 30) in his last appearance as US leader at the White House Correspondents' Association dinner, ending his performance with a mic drop and the words "Obama out".

The black-tie event - at which the President, followed by a bona fide comedian, regale journalists and their celebrity guests with insider jokes about government and the media - is an annual inside-the-beltway ritual that brings together journalists and media moguls with Hollywood stars and power brokers from Capitol Hill and beyond.

Mr Donald Trump, the 2016 Republican White House frontrunner and a frequent event guest, was absent on Saturday. He was the target of some pointed jabs at the 2011 dinner, and said he would not attend this year's event, suggesting that the media would misreport his mood.

Mr Obama took aim at Democrats and Republicans alike, but saved his sharpest barbs for Mr Trump.

"The Republican establishment is incredulous that he's their most likely nominee," Mr Obama told attendees.

"They say Donald lacks the foreign policy experience to be president. But in fairness he has spent years meeting with leaders from around the world: Miss Sweden, Miss Argentina, Miss Azerbaijan," the President said to howls of laughter, referring to contestants on the Miss Universe pageant that Mr Trump formerly co-owned.

Mr Obama made fun of the angst many in the Republican establishment have expressed at the prospect that Mr Trump or Tea Party candidate Ted Cruz could win the party's nomination to run in the Nov 8 presidential election.

"Guests were asked to check whether they wanted steak or fish, but instead a whole bunch of you wrote in Paul Ryan," Mr Obama said, referring to the top Republican in the House of Representatives, who many have hoped could be lured into running for president.

"That's not an option people," he said, displaying comedic chops perfected through seven previous appearances at the annual dinner. "You may not like steak or fish, but that's your choice."

Mr Obama made fun about how he has aged on the job and how in his final year his approval ratings have been rising.

"The last time I was this high, I was trying to decide on my major," Mr Obama said, a reference to smoking pot in college.

Billionaire Republican former New York mayor Michael Bloomberg, who toyed with the idea of entering the presidential race, was at the event, and Mr Obama told him: "Mike, a combative, controversial New York billionaire is leading the GOP primary and it's not you.

"That has to sting a little bit. Although it is not an entirely unfair comparison between you and The Donald. Mike was a big city mayor. He knows policy in depth, and he is actually worth the amount of money that he says he is."

Democratic presidential candidate Bernie Sanders was also present.

"Bernie, you look like a million bucks. Or, to put in terms you will understand, you look like 37,000 donations of US$27 each," Mr Obama told him, a reference to the flood of small contributions to Senator Sanders' insurgent campaign.

"I am hurt though, Bernie, that you have distanced yourself for me. That's not something that you do to your comrade."

In his remarks, Obama looked back on his presidency and jokingly predicted the country may be nearing its doom.

"The end of the republic has never looked better," the tuxedo-clad President said looking out at the well-groomed crowd as he blasted Republican Party Chairman Reince Priebus.

"Congratulations on all your success," Mr Obama told Priebus, while wearing a sarcastic grin. "The Republican party, the nomination process - it's all going great."

With a bit of nostalgia, Mr Obama reflected on his more than seven years in office, saying he had been a young man of idealism and vigor before he became president. "Eight years ago I said it was time to change the tone of our politics," Obama said. "In hindsight, I clearly should have been more specific."

On a serious note, he praised Washington Post former Teheran correspondent Jason Rezaian, released in October after 18 months in an Iranian prison.

Mr Obama ended his presentation by saying "Obama out" followed by a microphone drop, a celebrity and pop culture way of saying that the performance was so good there is nothing to add.

Mr Larry Wilmore, the host of a show on cable outlet Comedy Central, took his own shots at Mr Trump when he took the podium after Mr Obama, joking that next year the dinner will be called:"Donald Trump presents a luxurious evening paid for by Mexico."

Mr Trump has famously promised to build a wall between the United States and Mexico to prevent illegal immigration, and he has said he would force Mexico to pay for it.

Hollywood celebrities at the event included actors Will Smith and his wife Jada Pinkett Smith, Kerry Washington, star of the Washington-based TV show "Scandal", Helen Mirren, Bryan Cranston and singer Aretha Franklin.