March 3 (Bloomberg) -- Companies assisting the shipment of banned Iranian arms exports might face United Nations sanctions that would freeze their financial assets, Japan’s envoy to the
world body said.

“This is an important message,” Ambassador Yukio Takasu, chairman of the Security Council committee that monitors enforcement of UN prohibitions on Iranian weapons sales, said in
an interview. “Most of the companies are affiliated with
governments, but in some industrialized countries they are
private firms.”

Takasu is scheduled to highlight the vulnerability of companies to Iran sanctions during a Security Council briefing tomorrow. The panel is concerned about reports of ship owners,
insurance companies and cargo handlers being involved in
shipments that were seized and reported to the UN, he said.

“Instead of waiting for the government to be confronted by some kind of violation committed by companies registered in their country, there are things they can do,” Takasu said. “In
the banking system they are doing that already. Finance
ministers or banking authorities are informing all banks of
things they have to do.”

‘Vigilance’

UN resolutions ask governments to “exercise vigilance” over their financial institutions so that they avoid entering into relationships with Iranian banks that might aid the
nation’s nuclear program.

The UN caution to companies comes amid heightened pressure on businesses to cut ties to Iran, and as the U.S., Britain, France and Germany push for tighter UN penalties on the Islamic
government. The Western powers say Iran’s nuclear program is
intended to produce a weapons capability, a contention the
government denies.

The seizure last year of two ships allegedly transporting Iranian arms to Syria produced a committee request that governments “alert their private sector to this pattern of
sanctions violations and the risks involved in facilitating such
violations.”

UN resolutions apply to “persons and entities” that facilitate a violation, an advisory known as an Implementation Assistance Notice said.

The notice to Security Council members cited Malta’s seizure in October of bullet casings and other arms on the Hansa India, owned by Hamburg, Germany-based Leonhardt & Blumberg, and
the February 2009 interception by Cyprus of cargo including
explosives on the Cypriot-flagged Monchegorsk.

Leonhardt & Blumberg didn’t immediately respond to a request for a comment. The owner of the Monchegorsk hasn’t been identified.

Pressure from Activists

The New York-based group United Against Nuclear Iran has stepped up pressure on companies to sever ties to Iran, including business unrelated to its nuclear program. Peoria,
Illinois-based Caterpillar Inc., Munich-based Siemens AG and The
Woodlands, Texas-based Huntsman Corp. have announced that they
or their subsidiaries would no longer do business in Iran.

California’s insurance regulator last month asked insurers to stop investing in 50 non-U.S. companies, including Siemens and The Hague-based Royal Dutch Shell Plc, because of their work
in Iran’s energy, nuclear and defense industries.

United Against Nuclear Iran “applauds the Japanese ambassador to UN Security Council for calling attention to the need to enforce international sanctions against Iran,” Mark
Wallace, the group’s president, said in a statement.
“Corporations that continue to do business with Iran not only
undermine the will of the international community, they also
violate international law.”