He died at his home in California, according to the friend, who spoke on condition of anonymity. The friend said the family has turned to making funeral arrangements. A formal statement was expected later.
The White House was told his health had taken a turn for the worse in the last several days.
Five years after leaving office, the nation's 40th president told the world in November 1994 that he had been diagnosed with the early stages of Alzheimer's, an incurable illness that destroys brain cells. He said he had begun "the journey that will lead me into the sunset of my life."
Reagan body was expected to be taken to his presidential library and museum in Simi Valley, Calif., and then flown to Washington to lie in state in the Capitol Rotunda. His funeral was expected to be at the National Cathedral, an event likely to draw world leaders. The body was to be returned to California for a sunset burial at his library.
Reagan lived longer than any U.S. president, spending his last decade in the shrouded seclusion wrought by his disease, tended by his wife, Nancy, whom he called Mommy, and the select few closest to him. Now, Gerald Ford, Jimmy Carter, George H.W. Bush and Bill Clinton (news - web sites) are the surviving ex-presidents.
Although fiercely protective of Reagan's privacy, the former first lady let people know his mental condition had deteriorated terribly. Last month, she said: "Ronnie's long journey has finally taken him to a distant place where I can no longer reach him."
Reagan's oldest daughter, Maureen, from his first marriage, died in August 2001 at age 60 from cancer. Three other children survive: Michael, from his first marriage, and Patti Davis and Ron from his second.
Over two terms, from 1981 to 1989, Reagan reshaped the Republican Party in his conservative image, fixed his eye on the demise of the Soviet Union and Eastern European communism and tripled the national debt to $3 trillion in his singleminded competition with the other superpower.
Taking office at age 69, Reagan had already lived a career outside Washington, one that spanned work as a radio sports announcer, an actor, a television performer, a spokesman for the General Electric Co., and a two-term governor of California.
At the time of his retirement, his very name suggested a populist brand of conservative politics that still inspires the Republican Party.
He declared at the outset, "Government is not the solution, it's the problem," although reducing that government proved harder to do in reality than in his rhetoric.
Even so, he challenged the status quo on welfare and other programs that had put government on a growth spurt ever since Franklin D. Roosevelt's New Deal strengthened the federal presence in the lives of average Americans.
In foreign affairs, he built the arsenals of war while seeking and achieving arms control agreements with the Soviet Union.
In his second term, Reagan was dogged by revelations that he authorized secret arms sales to Iran while seeking Iranian aid to gain release of American hostages held in Lebanon. Some of the money was used to aid rebels fighting the leftist government of Nicaragua.
Despite the ensuing investigations, he left office in 1989 with the highest popularity rating of any retiring president in the history of modern-day public opinion polls.
That reflected, in part, his uncommon ability as a communicator and his way of connecting with ordinary Americans, even as his policies infuriated the left and as his simple verities made him the butt of jokes. "Morning again in America" became his re-election campaign mantra in 1984, but typified his appeal to patriotrism through both terms.
At 69, Reagan was the oldest man ever elected president when he was chosen on Nov. 4, 1980, by an unexpectedly large margin over incumbent Democrat Jimmy Carter.
Near-tragedy struck on his 70th day as president. On March 30, 1981, Reagan was leaving a Washington hotel after addressing labor leaders when a young drifter, John Hinckley, fired six shots at him. A bullet lodged an inch from Reagan's heart, but he recovered.
Four years later he was re-elected by an even greater margin, carrying 49 of the 50 states in defeating Democrat Walter F. Mondale, Carter's vice president.
Inspiration
