WASHINGTON/CARACAS, May 18 (Reuters) - The U.S. has assured the United Nations that it will shield a proposed UN-administered Venezuela humanitarian fund from creditors, people familiar with the matter said on Thursday, removing a key obstacle to getting the money flowing. Representatives of Maduro and the opposition announced agreement on the fund in brief negotiations in Mexico late last year meant to advance efforts to organize free elections in Venezuela. The fund is meant to aid ordinary Venezuelans suffering from economic and humanitarian crises. According to the four sources familiar with the matter, the U.S. notified the UN earlier this month that the funds would be safe from creditors. Dinorah Figuera, head of the Venezuelan opposition's legislature, said the U.S. move "opens the possibility that funds will reach the United Nations and open the door to negotiations."

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