Prime Minister Tony Blair (search) was treated at a London hospital Thursday for a slipped disc in his back but was expected to continue with his duties uninterrupted, his office announced.

Blair left the hospital after treatment to go to his country residence Chequers (search), his 10 Downing St. office said. The 52-year-old was not expected to require further treatment, and his work schedule should not change, a spokesman in the office said.

He said the condition would not affect Blair's intention to serve a full third term in office.

Dr. Andrew Platts, the radiologist who treated the prime minister, said he had been given an anti-inflammatory injection that would likely be enough to correct the problem.

Downing Street said in a statement that Blair, who just won re-election to a third term, had been suffering discomfort in his back for some months, and was referred by his general practitioner to the Royal Free Hospital in Hampstead, north London, where he had an outpatient appointment.

"The prime minister has been experiencing some back pain over the last couple of months," the statement said. "It has given him discomfort from time to time, but obviously hasn't stopped him doing his job."

A Blair spokeswoman said the prime minister, who is known as a fitness buff, thought he might have injured himself while working out in a gym.

Earlier Thursday, Blair met at his office with two key political players in the Northern Ireland peace process — Democratic Unionist party leader Ian Paisley and Sinn Fein leader Gerry Adams (search).

He plans a breakfast meeting at Chequers on Friday with European Commission President Jose Manuel Barroso.

Blair has had other health problems while in office. He underwent an operation last year to correct an irregular heartbeat, a condition for which he was also treated in 2003.

A slipped disc occurs when part of one of the discs separating the vertebrae in the spine escapes from its ring and sticks out through a gap between the vertebrae.

The condition generally develops gradually over time, and can worsen suddenly, said Dr. Frank Schwab, director of the Spine Center at Maimonides Medical Center, in New York City. He was not involved in Blair's treatment.

"You may find that your back is stiffer, achier, it's harder to do vigorous activity," Schwab said.

He said slipped discs generally do not require surgery, but sometimes several injections are needed to ease the pain. Those who have had the condition once are more likely to get it again.

People who have been treated for slipped discs are generally advised to avoid lifting things for three months and avoid lifting heavy objects indefinitely. Physical therapy can also be used to help get the disc back in place.