The U.N. agency that helps Palestinian refugees expressed concern on Friday over moves by the mayor of Jerusalem to close down its operations in the city. Mayor Nir Barkat said on Thursday he had developed a plan to end the Jerusalem operations of the United Nations Relief and Works Agency (UNRWA), which aids Palestinians displaced by the 1948 war of Israel’s founding and to millions of their descendants, and to replace them with Israeli services. UNRWA has faced a financial crisis since the United States in August announced it was cutting aid to the body, calling it an “irredeemably flawed...