Iran is expected to receive within weeks a first shipment out of up to 400 Chinese-made shoulder-fired air-defense missile launchers, three sources familiar with the deal said, as it rebuilds its defenses amid war with the United States.

The purchase, valued at $60-70 million, is one of Tehran’s largest-known efforts to strengthen its short-range air defenses since the outbreak of its war with the U.S. and Israel, which exposed gaps in Iran’s ability to protect military sites and strategic infrastructure.

The contract covers the purchase of between 300 and 400 man-portable air defense systems (MANPADs), including Chinese-made QW-12 and FN-16 missiles, the sources said.