ConocoPhillips said Tuesday it sold its stake in its Russian joint venture, leaving the country after more than two decades.

The energy company said it sold its 50% interest in Polar Lights Co. to Trisonnery Asset Ltd. for an undisclosed amount. The owners of Trisonnery couldn’t immediately be reached for comment. State oil company OAO Rosneft also recently sold its 50% stake in Polar Lights, Reuters reported last week.

ConocoPhillips...