Richard Holbrooke in 'Stable but Still in Very Critical Condition,' Says Clinton

WASHINGTON, D.C., Dec. 13, 2010— -- Secretary of State Hillary Clinton said today that Special Representative for Afghanistan and Pakistan Richard Holbrooke, her top aide for the region, is "stable but still in very critical condition" following emergency surgery over the weekend to repair a tear in his aorta.

"We appreciate the outpouring of support and concern that has been evidenced from around the world," she said from Canada, where she will meet with her counterparts from Canada and Mexico to discuss economic and security issues.

Holbrooke underwent 20 hours of surgery Saturday after doctors struggled to control bleeding after he suffered a tear in the major artery. State Department spokesman P.J. Crowley said in a statement Sunday night that Holbrooke submitted to additional procedures that day to improve circulation following the previous day's surgery.

Perhaps fearing the worst, Holbrooke has been joined by his family, and has received visits from top officials, including Secretary of State Clinton and Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, at George Washington University Hospital in Washington, D.C.

Many top officials from around the world, including Afghan President Hamid Karzai and Pakistani President Asif Ali Zardari, have called the ambassador's family to offer their support.

"His family is grateful for the outpouring of support and prayers coming in from his many friends, colleagues and leaders around the world," the State Department said in a statement.

According to Democratic sources, Holbrooke, 69, gasped and was clearly in medical distress when he fell ill on Friday while meeting with Secretary of State Clinton. He was said to have walked of her office unassisted before he was tended to by medical personnel at the State Department and transported to the hospital.

President Obama issued a statement Saturday night, offering his support for the envoy's family.

"Richard Holbrooke is a towering figure in American foreign policy, a critical member of my Afghanistan and Pakistan team, and a tireless public servant who has won the admiration of the American people and people around the world," Obama said.

Obama Offers Prayers for Holbrooke's Recovery

Holbrooke's hospitalization came days before the Obama administration was set to roll out its Afghanistan review Thursday.

Holbrooke was expected to be part of the public presentation, but aides told ABC News that the review is nearly complete and his absence should not affect its release.

Holbrooke was named to his current post days after Obama took office in January 2009, and he was immediately given the job of overhauling U.S. efforts in Afghanistan and Pakistan. He was best known for his bombastic personality and stamina, having traveled to the region numerous times since taking office.

The veteran diplomat is a former two-time assistant secretary of state, ambassador to Germany, and was a key player in the Dayton Peace accords, which brokered an end to the conflict in Bosnia.

Holbrooke began his long career as a foreign service officer at the U.S. Embassy in Saigon during the Vietnam War. ABC News' Jake Tapper, Ryan Creed and Kevin Dolak contributed to this report.