WASHINGTON – Warren M. Christopher, the lawyer turned envoy who tirelessly traveled to Bosnia and the Middle East on peace missions during his 1993-96 tenure as secretary of state in the Clinton administration, has died at age 85.

Christopher died late Friday at his home in Los Angeles of complications from bladder and kidney cancer, said Sonja Steptoe of the law firm O’Melveny & Myers, where Christopher was a senior partner

When he took over as secretary of state in the Clinton administration at age 68, Christoper said he didn’t expect to travel much. He went on to set a four-year mark for miles traveled by America’s top diplomat, including some two dozen trips to Syria alone in a futile effort to promote a settlement with Israel.

After carrying out the Clinton administration agenda abroad, the longtime Californian returned home for an active life in local and national affairs and with his law firm.

President Obama said Saturday that he mourned the passing of a man who proved to be a “resolute pursuer of peace” and dedicated public servant.

“Warren Christopher was a skillful diplomat, a steadfast public servant, and a faithful American,” the president said in a statement.

As Christopher prepared to step down in 1996 as secretary “for someone else to pick up the baton,” he said he was pleased to have played a role in making the United States safer.

Along with his peace efforts, he said that his proudest accomplishments included playing a role in promoting a ban on nuclear weapons tests and an extension of curbs on proliferation of weapons technology.

The loyal Democrat also supervised the contested Florida presidential recount on behalf of Vice President Al Gore in the 2000 presidential election. The Supreme Court, in a 5-4 vote, decided for the Republican candidate, George W. Bush.

While his efforts with Syria didn’t bear fruit, he was more successful in the negotiations that produced a settlement in 1995 for Bosnia, ending a war among Muslims, Serbs and Croats that claimed 260,000 lives and drove another 1.8 million people from their homes.

While Christopher often preferred a behind-the-scenes role, he also made news as deputy secretary of state in the Carter administration, conducting the tedious negotiations that gained the release in 1981 of 52 American hostages in Iran.

President Carter awarded him the Presidential Medal of Freedom, the nation’s highest civilian award. “The best public servant I ever knew,” Carter wrote in his memoirs.

Secretary of State Hillary Rodham Clinton said Saturday that she was saddened by the passing of a friend and a man who was one of the “giants who came before her.”

“As well as anyone in his generation, he understood the subtle interplay of national interests, fundamental values and personal dynamics that drive diplomacy,” she said in a statement from Paris.

James A. Baker III, who was a rival of Christopher’s during the 2000 Florida recount battle, said he admired him as a thoughtful diplomat and man of integrity.

“Regardless of whether he was an adversary or an ally, Warren Christopher always exhibited utmost integrity, sincere courtliness and a noble nature,” Baker said. “His character was special and exemplary in the dog-eat-dog world of politics.”

In private life, Christopher also served. Among many other things, he chaired a commission that proposed reforms of the Los Angeles Police Department in the aftermath of the videotaped beating by police of black motorist Rodney King in 1991. When four officers arrested for beating King were acquitted of most charges the following year, Los Angeles erupted in days of deadly rioting.

Examining years of police records after the riots, the Christopher Commission found “a significant number of officers” routinely used excessive force.

Numerous reforms were eventually put in place, including limiting the police chief to two five-year terms and having the chief appointed and supervised by a civilian commission.

On accepting Christopher’s resignation as the nation’s top diplomat, President Clinton said Christopher “left the mark of his hand on history.”

As Clinton considered a successor, Christopher offered the criteria he would apply if the choice was up to him.

“It would be somebody who has the capacity to provide forceful leadership, someone who has great tenacity, someone who has endurance and a lot of stamina,” he said.

In the skies over Africa and approaching his 71st birthday in October 1996, Christopher set a new mark for miles traveled by a secretary of state over four years, the normal length of a presidential term: 704,487 miles. The crew on his Air Force jet presented him with a congratulatory cake.