WASHINGTON, D.C.: Jesse Helms is once again holding President Clinton's foreign policy hostage, this time by threatening to block any hearings on Clinton's presumptive nominee for U.S. ambassador to Mexico, Massachusetts Governor William Weld. "On social issues, Weld is as far left as you can go in the Republican party," reports TIME Boston bureau chief Sam Allis. "And certainly that drives Helms up a wall. But this is just Helms' opening shot. It means he wants something from the White House." Helms used his position as Senate Foreign Relations Committee Chair to hold up the Chemical Weapons treaty until the Administration agreed to a long-sought reorganization of the State Department. This time around, Helms could be seeking concessions on drug policy towards Mexico, or to influence the debate on MFN renewal for China. "Helms will probably end up going along," Allis notes. "But not until he gets his pound of flesh."