WASHINGTON – The United States is poised to significantly expand its non-lethal military aid to the Syrian opposition as European nations weigh easing an arms embargo to potentially supply the rebels with arms and increase pressure on President Bashar Assad to step down.

The European Union arms embargo expires at the end of May and may be allowed to expire or be modified to only block weapons that are headed to Assad’s government.

If that happens, it will amount to a new threat to give weapons to the rebels, and test whether the Syrian president reacts to the increased pressure.

U.S. Secretary of State John Kerry is expected on Saturday to announce plans to give opposition forces up to $130 million in defensive military supplies — possibly including body armor, armored vehicles, night vision goggles and advanced communications equipment. U.S. officials said exactly what is given, and how much it will cost, will be determined at a Saturday meeting Kerry will attend in Istanbul, Turkey, of the Syrian opposition leadership and their main international allies.