The death of Sir Stuart Bell is a "huge blow", Labour leader Ed Miliband has said.
The 74-year-old Labour MP, who represented Middlesbrough for nearly three decades, lost a short battle with pancreatic cancer earlier on Saturday, his family said.
"Sir Stuart's death will come as a huge blow to his family and many friends and colleagues," Mr Miliband said as MPs from all sides saluted his courtesy and kindness.
While never serving as a minister, Sir Stuart was the party's Northern Ireland spokesman during the 1980s and a parliamentary aide to then Labour deputy leader Roy Hattersley. Later in his career he was handed a powerful role on the Commons Commission - the body responsible for running the House - and was knighted in 2004 for "services to Parliament". He played a central role during one of Parliament's most difficult periods, as the long-running scandal of MPs' expenses abuses finally emerged in 2009.
Mr Miliband said: "He spent the long years of opposition fighting for the Labour Party to regain power and championed, throughout his life, the many causes that were close to his heart. He resigned from the opposition front bench to pursue his calls for justice for the children and families of the Cleveland child abuse scandal.
"He served the House of Commons and the Church of England as the Church Commissioner, a position he held for thirteen years and was a passionate campaigner on European issues. The son of a north east miner, Stuart was fiercely proud to represent Middlesbrough. Stuart was a dedicated family man and had a formidable partnership with his wife Margaret. All our thoughts are with her and his children."
After a grammar school education, Sir Stuart was briefly a colliery clerk and newspaper reporter before becoming a barrister. He was a member of Newcastle City Council until he won Middlesbrough in 1983. He went on to hold the seat through seven general elections. An ardent pro-European, in 2006 he was awarded the Legion d'Honneur by the French president for his contributions to Anglo-French relations.
Labour former Europe minister Chris Bryant paid tribute to the "ardent and intelligent pro-European Labour MP" as parliamentary colleagues began to register their sorrow at his death via Twitter. Ian Swales, the Liberal Democrat MP for neighbouring Redcar, wrote: "Very sad to hear of the death of Stuart Bell MP. Always a total gentleman to me."
Former prime minister Gordon Brown said: "Sir Stuart Bell combined great expertise with sound judgment. He will be remembered for his commitment to Middlesbrough as a constituency MP and for his great enthusiasm for social justice, Europe and the best relations between church and state, where his contribution will never be forgotten. My thoughts are with Stuart's family."
Prime Minister David Cameron said Sir Stuart was "one of Parliament's great characters". Mr Cameron said: "Throughout his three decades in the House of Commons, he always stood up for those issues he cared most deeply about. A firm advocate of church matters as Second Church Estates Commissioner for 13 years, and a member of the House of Commons Commission over a very challenging decade, he will be remembered for his kindness and his courtesy towards Parliamentary colleagues."