UPI, Washington, April 24, 2010 — A growing number of companies worldwide say U.S. pressure has resulted in severed ties, stopped sales or scaled back business with Iranian firms.

The moves come as U.S. President Barack Obama seeks tough United Nations sanctions against Iran because, he and other Western leaders say, the country is seeking to develop the capability to build a nuclear weapon.

The New York Times reports the U.S. accounting firms PricewaterhouseCoopers and Ernst & Young said they had cut off affiliation with Iranian firms, weeks after a similar decision by KPMG.

Other companies that have reduced or ended business with Iranian firms include General Electric, Huntsman, Siemens, Caterpillar and Ingersoll Rand, the Times said.

Daimler plans to sell a minority share in an Iranian engine maker, an Italian firm does not plan to renew its gas contract with Iran and the Malaysian state oil company cut off gasoline shipments to Iran, following the lead of others, including Royal Dutch Shell and Vitol.

The companies’ moves will help isolate Iran as it pursues its nuclear program, current and former U.S. officials told the Times.

’No one of these actions is that significant,’ said Stuart Levey, the Treasury undersecretary, who leads the American effort to persuade firms to abandon Iranian ties. ’But the overall trend, if you analyze it with the increasing political isolation of Iran, could be very significant.’