Beijing ? China on Friday rejected U.S. accusations that a major Chinese conglomerate helped Iran’s missile program, insisting it opposes the spread of weapons of mass destruction.

Washington announced sanctions Thursday on Northern Industries Corp., which it said sent Iran unspecified technologies or materials that could help develop long-range missiles capable of carrying such weapons. Officials said the company’s goods were barred from U.S. markets for two years.

“The Chinese side’s company has not offered help to the relevant projects of Iran,” said a Foreign Ministry statement faxed to reporters. “The United States is imposing its own national policy on others for no good reason.”

The company, known as Norinco, was created in 1980 as a weapons maker and expanded into an array of businesses including manufacturing, construction and hotels.

A U.S. State Department spokeswoman, announcing the sanctions Thursday, also said Washington would take action against the Chinese government’s proliferation activities — the first such warning to accompany penalties against a Chinese company.

Beijing hasn’t signed the global treaty on sales of missiles and related technologies but agreed to abide by its restrictions.

“The Chinese government has consistently pursued a policy of opposing the proliferation of weapons of mass destruction and their carrier rockets,” the Foreign Ministry statement said.

Last July, Washington punished nine Chinese entities accused of transferring weapons technology or related goods to Iran. But the economic and political impact of sanctions on Norinco, a major Chinese exporter, threaten to be much greater.