WASHINGTON, November 5 (IslamOnline & News Agencies) - The United States warned U.S. firms not to take part in a commercial boycott of Israel proposed by 18 Arab nations, threatening them that joining the campaign could be punishable by hefty fines and other sanctions.

"The U.S. government is strongly opposed to restrictive trade practices or boycotts targeted at Israel," said Under Secretary of Commerce for Industry and Security Kenneth Juster.

"The Commerce Department is closely monitoring efforts that appear to be made to reinvigorate the Arab boycott of Israel and will use all of its resources to vigorously enforce U.S. anti-boycott regulations," Agence France-Presse quoted Juster as saying in a statement Tuesday, November 6.

The Commerce Department administers regulations prohibiting U.S. entities from participating in unsanctioned foreign government trade embargoes, including the Arab League boycott of Israel, and has levied more than 26 million dollars in fines and denied numerous export licenses to firms found in violation.

Juster’s comments came in response to a pledge made last week by 18 of the 22 members of the Arab League to "reactivate" a half-century-old ban on trade with Israel.

Meeting in Damascus, Syria, the Arab League's Boycott Office of Israel (BOI) said that it was "necessary to reactivate the Arab boycott of Israel and combat the importation of Israeli products to Arab countries."

"The economic boycott of Israel is a peaceful, legal and noble means of struggle against the enemy and is aimed at preserving security and peace," it said in a statement issued after four days of talks.

The meetings were skipped by the three League members with full diplomatic ties with Israel - Egypt, Jordan and Mauritania - and Somalia.

Arab states once boycotted not just Israeli firms themselves, but third-country companies which do business with the occupying state.

However, the indirect boycott has largely lapsed since the launch of the Middle East peace process in 1991, and the six-monthly meetings of the Damascus-based BOI do little but go through the motions.

The BOI held its first official meeting in eight years last October, where it drew up a list of 15 firms to be black-listed, but the list remained unpublished.