The United States announced Wednesday that it was imposing new sanctions related to Pakistan’s nuclear-armed long-range ballistic missile program, including against the state defense agency that oversees the program.

State Department spokesman Matthew Miller said in a statement that the measures imposed on the National Development Complex and three companies were imposed under an executive order that “targets proliferators of weapons of destruction mass and their vectors”.

The sanctions freeze all U.S. assets owned by the targeted entities and prohibit Americans from doing business with them.

Pakistan’s foreign ministry said in a statement that the US action was “unfortunate and biased” and would harm regional stability by “aimed at accentuating military asymmetries”, an apparent reference to the country’s rivalry with India , equipped with nuclear weapons.

A State Department fact sheet says the Islamabad-based NDC has sought to obtain components for the country’s long-range ballistic missile program and missile testing equipment.

It says the NDC “is responsible for the development of Pakistan’s ballistic missiles”, including the Shaheen family of missiles.

The research organization Bulletin of the Atomic Scientists claims that the Shaheen series of missiles are nuclear capable.

Pakistan conducted its first nuclear test in 1998, becoming the seventh country to do so. The Bulletin estimates Pakistan’s arsenal at around 170 nuclear warheads.

Islamabad has refused to sign the Non-Proliferation Treaty, the cornerstone of the international system intended to prevent the proliferation of nuclear weapons.

The other entities hit with sanctions were Affiliates International, Akhtar and Sons Private Limited and Rockside Enterprise, all located in Karachi, the fact sheet said.

Companies worked with the NDC to acquire equipment.

“The United States will continue to take action against the proliferation and associated procurement activities of concern,” Miller said.