In a rare move, Russia will boycott a UN Security Council meeting Wednesday with the EUs Political and Security Committee (PSC), diplomats said, a further sign of deteriorating relations between Moscow and its United Nations partners. According to a Russian diplomatic source speaking anonymously Tuesday, Moscows decision is linked to the situation in Ukraine, AFP said. A Western diplomat told AFP they had no memory of Russia boycotting a Security Council meeting since it invaded Ukraine on February 24. The annual informal meeting between the council and the PSC has not been held since 2019 due to the Covid pandemic. Wednesdays meeting is expected to address the EUs interaction with the UN in countries where both organizations are conducting operations. Since Russia invaded Ukraine, relations have rapidly declined between Moscow and other countries in the UN. Russia, which is one of the five permanent members on the Security Council, has been ousted from several UN bodies, including the human rights council. At a press conference Tuesday, US Ambassador to the UN Linda Thomas-Greenfield, whose country will assume the Security Council presidency in May, said the council continues to function normally. The council has been "extraordinarily successful" in "isolating Russia" since the end of February, she said. "Thats a significant success. We have been successful in unifying the voices condemning Russia in the General Assembly, but it came about because there was so much support for it in the Security Council," said Thomas-Greenfield, noting Russia had escaped condemnation by the council in late February due to its veto power. "Russia is isolated in the Security Council, and every time we have a discussion in the Security Council as it relates to Russia, they are on the defensive and we will continue to keep them on the defensive until they end their brutal attack on the Ukrainian people," she told reporters.