Former minister and Labour peer Frank Judd has died aged 86, the party has said.
Lord Judd served as an MP in Portsmouth from 1966 to 1979 and was a minister in the Wilson and Callaghan governments.
He was also a former director of Oxfam before being appointed a life peer in 1991.
The party's leader Sir Keir Starmer described him as "a great Labour internationalist who fought for peace, human rights and social justice".
"He will be missed by us all," he said on Twitter.
Lord Judd served as minister for the Royal Navy and overseas development as well as in the Foreign Office.
Baroness Angela Smith, Labour's leader in the House of Lords, said he was a "man of extraordinary personal generosity".
"Frank Judd was special. Whether as an MP, minister, peer or director of Oxfam, he never lost his passion for politics as a force for good," she said.
"His Labour Lords' colleagues both admired and had enormous affection for Frank, and we valued his friendship."
The chairman of the Labour Peers Group, Lord Toby Harris of Haringey, said Lord Judd was "much-loved and respected".
"He was indefatigable, participating vigorously on the issues that mattered to him right up until the last few days," he said.
"He was passionate about social justice and international development, both as someone who headed up aid agencies and as minister for overseas development."
"He was always supportive and kind. He will be sorely missed," he added.