BRUSSELS ― Hungary has signaled it will drop its long-standing opposition to Ukraine’s bid for EU membership, allowing it and Moldova to begin formal negotiations to join the bloc in the coming days, four diplomats told POLITICO. The opening of the first negotiating “cluster” — a formal step on the path to membership — is scheduled to take place during an intergovernmental conference in Luxembourg on June 15, three of the diplomats said. Kyiv and Chisinau applied for EU membership at the same