Washington, Aug 26 (DPA) Senator Edward Kennedy, who became the Kennedy family's political standard bearer after his brothers president John F. Kennedy and senator Robert Kennedy were assassinated, has died at 77 after battling brain cancer.

Kennedy died late Tuesday at his home in Hyannis Port, Massachusetts, his family said.

US President Barack Obama, whose race for his Democratic Party's nomination last year got a big boost from Kennedy's endorsement, early Wednesday paid tribute to his late mentor.

'An important chapter in our history has come to an end,' Obama said in a statement.

Kennedy died before his life-long push for US health care reform was realised. His absence from the increasingly contentious debate was felt by fellow Democrats as well as Republicans, with whom he had a long track record of compromise.

'This is the cause of my life,' Kennedy wrote in July in Newsweek magazine.

'It is a key reason that I defied my illness last summer to speak at the Democratic convention in Denver to support Barack Obama, but also to make sure, as I said, 'that we will break the old gridlock and guarantee that every American will have decent, quality health care as a fundamental right and not just a privilege',' he added.

Kennedy's absence at two key events in recent weeks - the funeral of his sister, Eunice, the founder of Special Olympics, and the presentation of the nation's highest civilian award, the Medal of Freedom, at Obama's White House - gave rise to increasing concern about his health.

Obama is vacationing on Martha's Vineyard, an island off the Massachusetts coast near Hyannis Port. But he had not been able to visit him due to Kennedy's deteriorating condition, broadcast reports said.

Obama joined the chorus of tribute for Kennedy's legislative accomplishments, noting that '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.