BP is exiting its 19.75% shareholding in Russian oil giant Rosneft, the firm said in a statement.
The company also confirmed that its chief executive, Irish man Bernard Looney, is resigning from Rosneft's board with "immediate effect".
Mr Looney said he had been "deeply shocked and saddened by the situation in Ukraine".
"It has caused us to fundamentally rethink BP's position with Rosneft. I am convinced that the decisions we have taken as a board are not only the right thing to do, but are also in the long-term interests of BP," Mr Looney added.
"Our immediate priority is caring for our great people in the region and we will do our utmost to support them. We are also looking at how BP can support the wider humanitarian effort.
The move comes after BP came under pressure from the UK Government to cut ties with Rosneft.
Business Secretary Kwasi Kwarteng held a virtual call with Mr Looney for around 20 minutes on Friday to discuss the company's position.
Mr Kwarteng said he welcomed BP's decision to exit its shareholding in Rosneft.
"Russia's unprovoked invasion of Ukraine must be a wake-up call for British businesses with commercial interests in Putin's Russia."
Rosneft is part-owned by the Russian government. BP had held the 19.75% stake in the firm since 2013.
