Tributes from across the political spectrum have been paid to the former Labour minister and welfare campaigner Frank Field, who has died at the age of 81. Lord Field, who dedicated his career in Westminster to tackling social issues, including child poverty and modern slavery, served as an MP for 40 years. Messages of support came from across the political divide, with praise for “a man of often uncomfortable principle” with an “unwavering moral compass”. In 2021, he revealed he had been diagnosed with terminal cancer when his speech was read out in the House of Lords to support a change in the law on assisted dying. Field was one of the longest-serving MPs in the Commons, only losing his seat in the 2019 general election after forming his own party. Tony Blair, under whose government Field served as welfare reform minister, said: “Frank had integrity, intelligence and deep commitment to the causes he believed in. He was an independent thinker never constrained by conventional wisdom, but always pushing at the frontier of new ideas. “Even when we disagreed, I had the utmost respect for him as a colleague and a character. Whether in his work on child poverty or in his time devoted to the reform of our welfare system, he stood up and stood out for the passion and insight he brought to any subject.” The former home secretary Priti Patel wrote on X: “Frank was a kind and compassionate man and a great parliamentarian. His unwavering moral compass, commitment to working cross-party and unshakable principles defined him and will be greatly missed.” Chris Bryant MP, the shadow minister for creative industries and digital, said Field was “a man of often uncomfortable principle [who] made our politics better”. The Conservative MP Tracey Crouch wrote: “I am genuinely devastated to hear that Frank Field has died. He was one of parliament’s nicest people. Kind, softly spoken & generous in praise. He has been v poorly so there is comfort knowing he is now at peace but he will be hugely missed.” The shadow health secretary, Wes Streeting, described Field as “a great parliamentarian, crusader for social justice and source of wise counsel”. He wrote: “What a blessing to have known him and benefited from his advice and kindness, even as his illness gripped him.” The former justice secretary and Conservative MP Robert Buckland, wrote: “Very sad to hear of the death of Frank Field. He made a unique contribution to public life. His blend of compassion, thoughtfulness, decency, shot through with steel, will be greatly missed.” A family statement, issued by his parliamentary office, said: “Frank Field (Rt Hon Lord Field of Birkenhead, CH) has died at the age of 81 following a period of illness. “Frank was director of the Child Poverty Action Group between 1969 and 1979, and the member of parliament for Birkenhead between 1979 and 2019. “During that time, he served as a minister for welfare reform and led the independent review on poverty and life chances. He also chaired the Commons work and pensions select committee (and its predecessor committee on social services and social security) as well as the joint committee on the draft modern slavery bill. Field was first elected as the Labour MP for Birkenhead in Merseyside in 1979. He was made a cross-bench peer in 2020, where he became Lord Field of Birkenhead, and two years later was made a member of the order of the companions of honour. He continued to serve on the boards of Cool Earth, Feeding Britain and the Frank Field Education Trust. Field was welfare reform minister in Tony Blair’s first government in 1997 and went on to chair the work and pensions select committee. He later resigned the Labour whip over antisemitism and “nastiness” in the party under Jeremy Corbyn’s leadership. He stood in the 2019 general election for his newly formed Birkenhead Social Justice party but lost the seat to Mick Whitley for Labour. Field died on Tuesday in a London care home. He gave his support to the assisted dying bill in 2021, which would make it legal for terminally ill adults in England and Wales to seek support to end their lives. In a statement read by Molly Meacher, who had tabled the bill, Field said: “I’ve just spent a period in a hospice and I’m not well enough to participate in today’s debate. If I had been, I would have spoken strongly in favour of the second reading [of the bill]. “I changed my mind on assisted dying when an MP friend was dying of cancer and wanted to die early, before the full horror effects set in, but was denied this opportunity.” His family said in their statement: “Frank is survived by two brothers. He will be mourned by admirers across politics but above all he will be greatly missed by those lucky enough to have enjoyed his laughter and friendship.”