Washington, July 28 (Reuters): The Bush administration has decided to impose sanctions on two Indian firms for missile-related transactions with Iran, US officials said .

The disclosure came after the US House of Representatives overwhelmingly agreed the US should sell nuclear technology to India and rejected a move by critics to delay the vote over concerns that Delhi had not sufficiently helped the US to contain Iran.

Congressional critics have accused the administration of withholding a conclusive word on sanctions against Indian firms until after the vote to avoid endangering its passage.

The US considers Iran ? patron of the Hizbollah militant group fighting Israel in Lebanon ?- a major international threat, accusing it of building nuclear weapons under the cover of an energy programme. Tehran denies the charge.

Under terms of the US Iran-Syria Non-Proliferation Act, “we are going to report to Congress about transactions by two private Indian companies with Iran,” one official said.

He and another official declined to identify the firms but one official said the transfers involve “dual-use items related to missiles”.

Previous sanctions included Indian firms that sold chemicals, controlled by the Australia Group of Nations seeking to limit the spread of chemical and biological weapons, to Iran’s missile-production industry.

While the administration is mandated by law to report violations of the act to Congress every six months, sanctions are discretionary but won’t be waived in these cases, the other official said.

The officials did not specify the exact sanctions to be imposed but companies have previously been barred from receiving US government contracts, assistance or military trade as well as certain controlled goods with both civilian and military purposes.

The nuclear agreement is viewed as the cornerstone of an evolving strategic alliance between India and the US, former Cold War adversaries.

The US administration has repeatedly defended India as having an excellent record of protecting sensitive technology.

According to lawmakers, the US since 2003 has filed at least eight non-proliferation sanctions against at least seven Indian companies or persons, including two sanctions in December 2005. The new sanctions would add to that tally. By comparison, Chinese companies have been sanctioned 70 times in the past six years.

The information on the Indian firms is in a report that was due to be sent to Congress last October 1 and covers activities during the first half of 2005, one official said. Under-secretary of state Nicholas Burns decided on the sanctions earlier this week.

A US official insisted the administration tried to get alert Congress to the decision before the House vote. But a congressional aide said he only was told the report was coming and no details were provided.

“Clearly they were waiting for the House to vote on the nuclear agreement,” the aide said.

He predicted that if the sanctions were known, the House would not have defeated 235 to 192 a proposal to defer voting on the nuclear deal until India co-operated more on curbing Iran’s nuclear ambitions.

US officials said that since the US and India agreed last July to negotiate the nuclear deal and forge closer ties, New Delhi has increasingly co-operated against Iran.

They also predicted that as India implements its own new laws and international non-proliferation standards that are related to the nuclear deal, its firms would also comply.