A top Romanian court has validated the first round of a presidential race in which a far-right outsider emerged as the frontrunner, plunging the country into a week of turmoil amid allegations of electoral violations and Russian meddling.

Romania's Constitutional Court on Monday validated the shock first-round result in its presidential election, setting the stage for a run-off vote on Dec. 8 that could upend the country's pro-Western orientation and erode backing for Ukraine.

Romania's ruling leftist Social Democrats (PSD) looked set to win the most votes in a parliamentary election on Sunday, fending off a resurgent far-right movement that challenges the country's pro-Western orientation,