WASHINGTON (Reuters) – President Barack Obama served as comedian in chief on Saturday night, predicting that his second 100 days in office will be so successful that he will wrap them up in record time.

"I must confess I really did not want to be here tonight," Obama told guests at the White House Correspondents' Association dinner -- an annual black-tie gathering of journalists, politicians and Hollywood celebrities. "But I knew I had to come. That's one more problem that I inherited from George W. Bush."

Alluding to his reputation for staying cool and on message, Obama ticked off a series of goals he hoped to achieve.

In the next 100 days, he said, he would learn to go off the teleprompter and Vice President Joe Biden, famous for verbal gaffes, "will learn to stay on the prompter."

Obama said he also expected to house-train his new, seven-month-old Portuguese water dog, Bo.

"The last thing Tim Geithner needs is someone else treating him like a fire hydrant," he said, referring to his treasury secretary. Geithner was forced to pay $34,000 in unpaid back taxes before being confirmed to his job and he has been criticized for his handling of the financial crisis.

"Finally, I believe that my next 100 days will be so successful that I will be able to complete them in 72 days. And on the 73rd day, I will rest," he joshed.

In a dig at the press, Obama said: "We look for you for truth -- even if it's always an approximation."

Obama later endured some ribbing from stand-up comic Wanda Sykes. She shared the head table at the dinner that brought together some 2,700 people at the $200-a-plate event -- proceeds of which went to charity and to fund journalism scholarships.

Sykes, known for her blunt take on current events, mused about her pride in Obama's being the country's first black president.

"That's unless you screw up," she said, turning to him from the podium. "And then it's going to be -- what's up with the half-white guy."