WASHINGTON — The House brushed aside the objections of the Clinton Administration on Thursday and voted overwhelmingly to tighten the U.S. trade embargo against Cuba and slap secondary sanctions on countries that help Fidel Castro's regime.

Supporters of the legislation said it will hasten Castro's downfall by drying up Cuba's remaining sources of hard currency, despite Secretary of State Warren Christopher's warning that the measure will stifle U.S. efforts to foster peaceful change in Cuba and jeopardize U.S. interests around the world by requiring action against Russia and other countries that deal with Havana.

About the same time the House was moving to restrict the Administration's ability to maneuver in its relations with Cuba, the Senate sought to give President Clinton new latitude in dealing with Pakistan by approving a White House request to ease the U.S. arms embargo on Islamabad. The sanctions were imposed five years ago because of Pakistan's suspected nuclear weapons program.

The Senate legislation, adopted as an amendment to a larger foreign aid bill, would permit the Administration to deliver $368 million worth of military equipment, including antiaircraft and anti-ship missiles, that Pakistan purchased in 1990 but never received. The measure would not allow Pakistan to take possession of 28 F-16 warplanes, for which it already has paid $1.4 billion, but it would authorize the Administration to sell the aircraft and give Pakistan the proceeds.

Officials said the planes are unlikely to sell for anything close to the original price because they are already 5 years old and because production of spare parts is scheduled to end within a few years.

The Pakistan measure, which lasts for just a year, was approved by a 55-45 vote as an amendment to the $12.4-billion foreign aid bill, which the Senate passed later in the day. The bill, which was passed by a 91-9 vote, will now go to a conference committee to reconcile differences with the House, which voted about $400 million less and did not consider the Pakistan proposal.

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The Cuba sanctions measure was approved 294 to 130, with 67 Democrats joining all but four Republicans in support. A similar Senate measure by Sen. Jesse Helms (R-N.C.) has not been acted upon. Christopher has said he will recommend that Clinton veto the bill if it reaches his desk.