KYIV, Ukraine — About 5,000 ultra-right activists marched across the Ukrainian capital Wednesday to denounce a cease-fire in the conflict with Russia-backed separatists in eastern Ukraine, leaving an anti-Semitic banner pinned to the presidential office's entrance.

Ukrainian President Volodymyr Zelenskiy has sought to intensify efforts to end the fighting with Russia-backed separatists in the east, championing a cease-fire that has largely held for more than 2 1/2 months despite occasional clashes.

On Wednesday, Zelenskiy visited the Ukrainian troops in the east, hailing the truce and voicing hope that it will help end the conflict.

But the right-wingers who rallied in the Ukrainian capital denounced the cease-fire deal as a betrayal of Ukrainian interests. They also demanded new legislation to counter those whom they described as "collaborationists" sympathetic to Russian interests, including several TV stations they said must be shut.

After rallying outside the presidential office, the far-right activists pinned a huge banner denouncing what they described as the "occupation and pilfering of Ukraine" by the president's "Jewish clan" to the building's entrance.

The United Jewish Community of Ukraine demanded that prosecutors open a probe into what it described as an anti-Semitic act.

There was no immediate reaction from Zelenskiy's office.

The two ex-Soviet neighbors have been locked in a tug-of-war after Russia annexed Ukraine's Crimean Peninsula in 2014 following the ouster of the former, Moscow-friendly Ukrainian president and cast its support behind separatist insurgents in eastern Ukraine.