U.S. President Barack Obama shares a laugh with Senator Edward Kennedy before signing the Serve America Act in April 2009. (Jason Reed/Reuters)Edward Kennedy was applauded for his dedication to life-long causes, including peace talks and health care, as tributes to the American senator poured in on Wednesday.

Kennedy — called Ted by his family and friends — died late Tuesday night at his Cape Cod home following a year-long battled with brain cancer. He was 77.

"An important chapter in our history has come to an end. Our country has lost a great leader, who picked up the torch of his fallen brothers and became the greatest United States senator of our time," said U.S. President Barack Obama in a written statement issued shortly after the senator's death.

The Massachusetts senator will be buried at Arlington National Cemetery alongside his slain brothers, former U.S. president John F. Kennedy and senator Robert Kennedy.

He will lie in repose on Friday, while his funeral service will be held Saturday, an Obama administration official told Reuters. A source told The Associated Press that Obama will eulogize Kennedy at his funeral mass.

Obama later took a break from his family vacation on the Massachusetts island of Martha's Vineyard to hold a news conference Wednesday morning to pay tribute to Kennedy.

"We've seen the courage with which he battled his illness, and while these months have no doubt been difficult for him, they've let him hear from every corner of our nation and around the world just how much he meant to all of us," Obama said.

Obama called Kennedy a "singular figure in American history."

Known as the liberal lion of the U.S. Senate, Kennedy was the third-longest serving senator in American history and was a steadfast champion of the working class and the poor and known as a powerful voice on health care, civil rights, war and peace.

"For five decades, virtually every major piece of legislation to advance the civil rights, health and economic well-being of the American people bore his name and resulted from his efforts," said Obama, who received Kennedy's endorsement in the 2008 Democratic primary.

Congressional dealmaker

Kennedy was known for his ability to work across partisan divides and was seen as a consummate congressional dealmaker.

U.S. Senator Edward Kennedy talks with President Ronald Reagan during a fundraising event in 1985. (Charles Tasnadi/Associated Press)Kennedy was "an unwavering advocate for the millions of less fortunate," said former president Jimmy Carter, who beat Kennedy for the 1980 Democratic presidential nomination.

His more than 47 years of work in the Senate saw him author more than 2,500 bills, including the landmark 1990 Americans with Disabilities Act, Meals on Wheels for the elderly, abortion clinic access, family leave and the Occupational Safety and Health Administration.

"No one has done more than Senator Kennedy to educate our children, care for our seniors, and ensure equality for all Americans," said Democratic Speaker of the house Nancy Pelosi.

His work garnered an outpouring of condolences from the Republican and Democratic parties in the U.S.

"Given our political differences, people are sometimes surprised by how close Ronnie and I have been to the Kennedy family," said Nancy Reagan, widow of Republican president Ronald Reagan.

But Kennedy was always willing to find a common ground, Reagan said, calling him "an ally and a dear friend."

'Larger-than-life'

Kennedy "was an iconic, larger-than-life United States senator whose influence cannot be overstated," said Republican Senator Orrin Hatch.

He was also a key negotiator on legislation creating a Medicare prescription drug benefit for senior citizens and was a driving force for peace in Ireland and a persistent critic of the war in Iraq.

"Teddy inspired our country through his dedication to health-care reform, his commitment to social justice and his devotion to a life of public service," said California Gov. Arnold Schwarzenegger, who is married to Kennedy's niece, Maria Shriver.

"Teddy taught us all that public service isn't a hobby or even an occupation, but a way of life, and his legacy will live on," Schwarzenegger said.

Senate majority leader Harry Reid promised that Congress, while mourning Kennedy's loss, would renew the push for the cause of Kennedy's life — health-care reform.

"The liberal lion's mighty roar may now fall silent but his dream shall never die," Reid said.

International achievements

Even facing illness, Kennedy never stopped fighting for "the causes which were his life's work," said British Prime Minister Gordon Brown. Kennedy received an honorary knighthood from Britain earlier this year.

Kennedy "made an extraordinary contribution to American politics, an extraordinary contribution to America's role in the world," said Australian Prime Minister Kevin Rudd.

The senator was the last brother of the Irish-American political Kennedy dynasty and played an important role during Northern Ireland's peace process in the 1990s.

He worked "valiantly for the cause of peace on this island," said Irish Prime Minister Brian Cowen. "America has lost a great and respected statesman and Ireland has lost a long-standing and true friend."

Italian President Giorgio Napolitano said in a statement that Kennedy "has left a deep mark and deserves the homage of all the free world."

Canadian Prime Minister Stephen Harper's office issued a one-line statement expressing "his sympathies and condolences to the family and friends of Senator Ted Kennedy."

Former prime minister Brian Mulroney said Kennedy always cared about Canadian issues and often shared similar viewpoints with Canadians. He called Kennedy one of the most outstanding U.S. legislators of the modern era.

Former Canadian NDP leader Ed Broadbent, who met Kennedy several times during the 1980s and 1990s, told CBC News the senator was "an absolutely extraordinary man with great conviction but also ... great capacity for getting things done. He didn't want to just win debates, he wanted to achieve great things and he did."

"We have all lost the most progressive and effective political voice for the left in American politics," Broadbent said.

With files from The Associated Press