Members of Congress have sharply questioned Bush administration officials about U.S. strategies to deal with Iran's suspected efforts to develop nuclear weapons. VOA's Dan Robinson reports, U.S. officials stressed to a congressional committee Thursday obstacles they say Iran continues to place in the way of progress regarding its nuclear programs, and support for terrorism.

It was another opportunity to vent frustrations about what some lawmakers see as ineffective U.S. and international diplomatic efforts, and voice concerns about threats posed by Iran.

While remaining committed to diplomatic efforts, working with international partners, President Bush has also stressed that the military option has never been taken off the table.

In written testimony, Jeffrey Feltman, Principal Deputy Assistant Secretary of State for Near Eastern Affairs, underscored this describing military action as a last resort.

He reiterated the administration's assessment of continuing dangers posted by Iran's nuclear program.

"Iran's leadership remains committed to two key elements of building a nuclear weapon: acquisition of high-grade nuclear material and development of a capable delivery system," saidJeffrey Feltman. "Tehran can re-start the third element, weaponization [at] any time and conceivably could already have taken that step."

Feltman pointed to efforts of the P5 + 1 group comprising the U.S., Britain, China, France, Russia, and Germany involving dual-track strategies to escalate pressure on Tehran, through the U.N. Security Council and unilateral economic sanctions, to abandon any long-term nuclear weapons work, while offering political, economic, technological and other incentives.

Democrat Gary Ackerman isn't satisfied, asserting along with a number of other House Democrats that, in his words, a slow motion multilateral diplomatic track has produced no change in Iranian behavior.

"The multilateral sanction effort is moving at a glacial pace," said Gary Ackerman. "Iran's [uranium] enrichment program is in the home stretch and sprinting. We're moving in inches and they are advancing in yards. The mullahs are not only ahead in this race, they are expanding their lead."

Lawmakers have been assessing the latest statements by Iranian president Mahmoud Ahmadinejad, including some describing the September 11, 2001 al-Qaida attacks on the U.S. a suspect event.

Republican Mike Pence calls the Iranian leader's remarks bizarre [and] offensive, and refers to other Iranian statements about uranium centrifuge operations.

"Iran's nuclear intentions can not be ready in anything but the most ominous light," said Mike Pence. "Now the subject of four U.N. Security Council resolutions as recently as March 3, 2008 this is a state more than willing to harm itself economically in order to advance a nuclear program that cannot be viewed as peaceful."

Deputy Assistant Treasury Secretary for Terrorist Financing and Financial Crimes, Daniel Glaser, responded to skeptical lawmakers, insisting that U.S. and international steps are having an impact.

"With mounting evidence of Iran's elicit behavior, the international financial community that doing business with Iran is too risky," said Daniel Glaser. "The world's leading financial institutions have largely stopped dealing with Iran and especially Iranian banks in any currency. Iranian financial institutions and businesses have been left with decreased access to private international financial institutions and a lessened ability to attract international investment and capital.

Glaser describes possible future action against Iran's central bank as one of a number of options to pressure Iran, but said doing so would be an extraordinary step.

Congressman Brad Sherman is a leading voice among Democrats who accuse the Bush administration of failing to enforce provisions of the Iran Sanctions Act, and undermining other congressional efforts.

"We have a law that requires at a minimum the administration to identify, name and shame the companies involved," said Brad Sherman. "To not take that action is to violate American law [in order] to protect Tehran and its business partners."

Responding to questions on Iran in Thursday's hearing, Ambassador Feltman also issued a strong warning regarding Iranian actions in support of instability in Iraq.

While the U.S. would like to see a peaceful relationship between Iran and Iraq, Feltman said make no mistake, the U.S. will act to protect its interests, our troops and our Iraqi partners.