CARACAS, Dec 5 (Reuters) - Julio Borges, the politician who serves as foreign minister for Venezuela"s U.S.-backed interim government, said on Sunday he would leave his post, further weakening the opposition just weeks after it was routed in regional elections. The United States and dozens of other countries recognize the interim government, led by Juan Guaido and formed at the beginning of 2019, and consider the 2018 re-election of President Nicolas Maduro to be fraudulent. The interim government is not serving its purpose, Borges, whose differences with Guaido are well-known, said in an online press conference. "The (interim) government makes sense as an instrument to get out of the dictatorship, but at this moment, in our way of seeing it, the interim government has been deformed," Borges said. "Instead of being an instrument to fight the dictatorship, the interim government has become a kind of ... caste," he said. Borges lives in Bogota, the capital of neighboring Colombia, where he was granted political asylum after Maduro"s government accused him of being part of a plot against the president. He is a member of the First Justice party, one of the four major opposition parties and part of Guaido"s coalition in the national assembly. Neither First Justice nor Guaido"s office immediately responded to requests for comment. Borges said he will make his resignation official during a legislative session on Tuesday and that the interim government should "disappear." It should only serve to manage foreign-based state assets like U.S.-based refiner Citgo and its political structure must be rejigged, he added. Internal divisions within the opposition and slow alliance agreements between parties are seen by analysts and some members of the opposition itself as one of the causes of losses in local and regional elections in late November, when opposition candidates won just three of 23 governorships.