East Belfast MP Gavin Robinson has backed a campaign calling for parliamentary pensions to be made free of fossil fuel investments.
The DUP MP has joined a cross-party group of over 200 serving and former MPs who want the Parliamentary Contributory Pension Fund (PCPF) to phase out its substantial investments in fossil fuel giants, including almost £11m of shares in Shell and £11.7m in BP.
More than a third of MPs are calling for investments in the PCPF to move away from fossil fuels and towards renewables.
Some 221 sitting and 28 former politicians signed up for the campaign, which is led by former energy secretary Ed Davey and Green MP Caroline Lucas.
It was established amid growing concern about the environmental, social and financial risks posed by climate change.
Mr Robinson became the first MP from Northern Ireland to sign Westminster's cross-party Divest Parliament Pledge after meeting concerned constituents, including a new mother and a school pupil.
He also received a number of letters about the PCPF's policy regarding investments in fossil fuel companies.
Mr Robinson said politicians from all corners of the UK needed to take urgent action to press for further reductions in carbon pollution caused by the burning of fossil fuels.
"Pension funds need to stop investing in companies that aren't committed to bringing about a clean-energy future," the East Belfast MP stressed.
His constituent Helen Newell added: "Political leaders should not be investing in fossil fuels through their pensions when the climate science is unequivocal.
"The vast majority of fossil fuels must stay in the ground to contain global warming between 1.5 and two degrees.
"We must invest in a world powered by clean energy to create jobs, improve our health and tackle climate change."
The campaign was started in 2014 by a small group of MPs.
The group's first taste of success came when it pressured the trustees of the PCPF to disclose its investments, which revealed the largest individual holding was in BP.
If successful, the campaign would see Parliament joining investors such as the Church of Ireland and Queen's University Belfast in committing to fossil fuel divestment.
It comes after the Belfast Telegraph revealed in March that a major pension fund for local public sector workers had millions of pounds tied up in controversial investments.
The Northern Ireland Local Government Pension Scheme was found to have shares in businesses linked to fracking, alcohol, the tobacco industry, the arms trade and companies heavily criticised for not paying enough tax.
Analysis of the committee's equity holdings showed investments totalling more than £2.2bn in approximately 600 companies.
The scheme is managed by the Northern Ireland Local Government Officers' Superannuation Committee (NILGOSC), which said its main duty was to act in the interests of the scheme's beneficiaries.
The NILGOSC manages the pensions of 118,000 people across approximately 200 organisations, including councils, schools and the Northern Ireland Fire and Rescue Service.