LONDON (AP) — The Scottish National Party brought an end to its three-year power-sharing agreement with the much smaller Greens on Thursday after tensions grew between the two pro-independence parties over climate change policies.

Humza Yousaf, Scotland’s first minister, informed the Greens he was terminating 2021’s Bute House Agreement, which was signed by his predecessor Nicola Sturgeon, with immediate effect.

The move means Green co-leaders Lorna Slater and Patrick Harvie are no longer part of the Scottish government, and that the SNP will be operating as a minority administration. To get legislation and the budget through Parliament, it will have to rely on votes from other parties. Of Parliament’s 129 seats, the SNP holds 63, two short of a majority, while the Greens have seven.

“It is no longer guaranteeing a stable arrangement in Parliament, the events of recent days have made that clear, and therefore, after careful consideration, I believe that going forward it is in the best interest of the people of Scotland to pursue a different arrangement,” Yousaf said a news conference in Edinburgh.