The UK is to rejoin the EU's flagship scientific research scheme, Horizon, the government has announced.
UK-based scientists and institutions will be able to apply for money from the £81bn (€95bn) fund from today.
Associate membership had been agreed as part of the Brexit trade deal when the UK formally left the EU in 2020.
However, the UK has been excluded from the scheme for the past three years because of a disagreement over the Northern Ireland Protocol.
Prime Minister Rishi Sunak said: "With a wealth of expertise and experience to bring to the global stage, we have delivered a deal that enables UK scientists to confidently take part in the world's largest research collaboration programme.
"We have worked with our EU partners to make sure that this is the right deal for the UK, unlocking unparalleled research opportunities, and also the right deal for British taxpayers."
Thursday's announcement also states that the UK will associate to Copernicus, the EU's £8bn (€9bn) Earth observation programme. Britain will not, however, be rejoining a nuclear research alliance known as Euratom R&D, although there is an agreement to cooperate specifically on nuclear fusion.
In a press release, the European Commission said that the decision would be "beneficial to both" and stated that "overall, it is estimated that the UK will contribute almost €2.6bn (£2.2bn) per year on average for its participation to both Horizon and Copernicus.