NATO and US demands to withdraw Russian troops from Transnistria are contrary to international law. According to Washington, Russian troops are stationed there without the consent of the host and undermine European security.
A recurring pro-Kremlin narrative about Russian troops in the Transnistrian region of the Republic of Moldova, trying to draw attention away from the real issue.
In this breakaway region, uncontrolled by the constitutional authorities of Moldova, there is a contingent of the Russian army, called the Operational Group of Russian Forces. There is also a Russian ammunition and weapons depot in the region. After the 1992 armed conflict in the region, Moldova is constantly demanding the withdrawal of Russian troops and ammunition from its territory.
By signing the final document of the OSCE summit in Istanbul in 1999, Russia has pledged to withdraw ammunition and troops by 2002 but has not done so to date. Since then, Russia has been repeatedly asked to honour its commitment and withdraw its troops from Moldova. In June 2018, the UN General Assembly adopted a statement urging troops withdrawal from the Republic of Moldova.
Also, in June 2021, the heads of state and government participating in the meeting of the North Atlantic Council in Brussels issued a communiqué with the same requirement to Russia.
See here a similar case claiming that Romania and Moldova have a secret plan to forcefully push Russian troops out of Transnistria.