Iranian technicians work at a facility near Isfahan, south of Tehran, that produces uranium fuel for a heavy-water nuclear reactor (File)Diplomats from the United States, France, Russia and the United Nationsare scheduled to meet with Iranian officials next Monday, October 19,in Vienna to resume discussions about the country's nuclear program. But some Middle East analysts are looking at possible options shouldthe talks fail, including the possibility of severe sanctions or evenmilitary action.

Monday's talks are expectedto focus on a proposal to ship a large percentage of Iran's stock oflow-enriched uranium to Russia and France for conversion to fuel for anuclear reactor.

Western diplomats consider such a move to be aconfidence building measure since the uranium shipped back to Iranwould be used for civilian purposes and would be enriched below thelevel needed for nuclear weapons.

Middle East analyst DavidMakovsky of the Washington Institute for Near East Policy supports theObama administration's decision to negotiate with Iran, even if thetalks are unsuccessful.

"We don't know if engagement willwork," he said. "But we think even if it does not work as a strategy,as a tactic it is useful to basically frame all our other policyoptions. They will be viewed as more legitimate, more credible,because we will have tried."

The latest round of talks comesdays after the U.S. House of Representatives approved legislationmaking it easier for state and local governments to curtail investmentsin companies doing business in Iran's energy sector.

It is one of several bills introduced in Congress designed to pressure Iran about its nuclear program.

Senator Joe LiebermanSenator Joe Lieberman supports tougher sanctions on Tehran.  

"Myown belief is that the current Iranian leadership, the fanatical regimethat governs from Tehran, will only consider stepping back from thenuclear brink when they are convinced that if they fail to do so therewill be consequences so severe that the continuity of their regime willbe threatened," he said.

Lawmakers in Congress have called forstronger sanctions on Iran since it was revealed the government isworking on a previously undisclosed uranium enrichment facility nearthe holy city of Qom.

The International Atomic Energy Agency is scheduled to inspect the facility later this month.

"Wefound this facility in Qom, are there other secret facilities that areout there? Could they be spinning this amount of uranium somewhereelse? This is something that is another key factor that needs to beaddressed," said Middle East analyst David Makovsky.

While theObama administration is committed to diplomacy with Iran, it is alsopursuing a parallel track of seeking approval for harsh new sanctionsin an effort to prevent Tehran from dragging out the negotiations.

Sofar, both Russia and China have not backed new sanctions, despiteefforts by the administration to convince those countries that withoutsuch a threat Iran has less incentive to make concessions.

KennethPollack, a former CIA intelligence analyst on Iranian military issues,argues that even new sanctions are not likely to have an impact that issignificant enough to force Tehran to stop enriching uranium.  

"Myfear is that we may get something, but that it is not going to beenough and when that happens the entire policy is going to be revealedas having been a façade," he said.

Pollack says he has supportedengagement with Iran for at least a decade, but now thinks it may betime to isolate the government.

"The most useful thing that theUnited States could do for the Iranian people, for the oppositionmovement, is to isolate the regime, is to not give it the benefit, thelegitimacy of being recognized by the international community," he said.

MichaelO'Hanlon, a senior fellow with the Brookings Institution, goes a stepfurther, suggesting financial sanctions backed by a naval blockadecould be used to contain the Iranian government.

"This can bedone in a way that tightens up your economic sanctions," he said. "Thatperhaps someday tightens up a ban on Iran doing gasoline importation. There is a lot to be said for this option because it returns the onusback to Iran to initiate the use of force."

The Obamaadministration has not set any specific timelines for Iranian action,but has made it clear the U.S. will not negotiate indefinitely. TheU.S. and other major powers are concerned Iran is seeking a nuclearweapons program. Tehran insists its program is peaceful and forcivilian use.