Q+A - How will Iran deal with fresh sanctions?

LONDON (Reuters) - The U.N. Security Council has voted for a fourth round of sanctions aimed at curbing Iran's nuclear programme, which the West fears could lead to nuclear weapons.

Iran, the world's fifth-largest crude oil exporter, says its nuclear programme is a peaceful bid to produce electricity and has dismissed the new measures as ineffective.

How will Iran be able to cope with fresh sanctions, and will it find ways to bypass them? Below are some questions and answers on the issue.

WHAT IMPACT HAVE PREVIOUS SANCTIONS HAD ON IRAN?

The combination of U.N. and U.S. sanctions has hurt Iran's economy, making it more difficult for the Islamic Republic to import and export a range of commodities and to develop not just its nuclear industry but also its oil and gas sectors.

"It's not like there is a watertight seal around Iran. There is still business moving, but it's become harder and harder and more expensive," said Samuel Ciszuk, senior energy analyst for the Middle East and North Africa with consultancy IHS.

"The inflow of technology has been more or less stymied and finance is very hard to get. The brain drain continues to be a Umajor problem," he added.

A number of oil companies, trading houses and other international companies have stopped doing business with Iran this year in response to a U.S. drive to isolate Tehran.

"Sanctions have hit the Iranian government, and one of the consequences has been that the cost of imported goods is higher," Iran analyst Meir Javedanfar said.

"Its nuclear programme has moved at a much slower pace and the aviation sector has suffered greatly because they can't buy new planes with American technology."

HOW HAS IRAN COPED?

While U.S. companies and international firms with U.S. interests have pulled back, previous sanctions did not deter other companies from regions such as Asia.

Iran also has previously used trading hubs such as Dubai, Singapore and Hong Kong to get past restrictions on trade. Trade sources say Hong Kong has been used as a location to conduct U.S. dollar transactions in the past albeit at a higher cost.

Analysts say Iran has also used shell companies to trade and operate in places including offshore locations.

The U.S. Treasury this week announced it was targeting companies that it described as fronts for Iran's state shipping company IRISL. It said IRISL had "desperately attempted" to evade previous sanctions by renaming vessels and even repainting vessels to "hide their true ownership."

Iran's Supreme National Security Council, which coordinates defence and security policy, said on Friday any action "against legal and legitimate interests of the Iranian nation will in return receive a legal response and appropriate action of Iran."

HOW WILL IRAN MEET ITS GASOLINE NEEDS?

Previous U.S. sanctions have meant Iran has suffered from lack of investment in refineries, forcing the OPEC member to import some 40 percent of its gasoline needs.

While many international companies are likely to pull back further from engaging in trade deals with Iran, analysts and trade sources expect other suppliers, especially in Asia, to provide Iran with imports.

Iran had previously been able to ship gasoline from Middle East Gulf ports such as Jebel Ali and Sohar.

A trade source said that, with more scrutiny on ships transiting the region, Chinese firms and other Asian suppliers were likely to provide gasoline cargoes from Singapore.

"The Far East is an ideal supply option," the source said.

Through buying cargoes on a free on board (FOB) basis, the end destination of a ship does not need to be declared, the source said.

"With many FOB cargoes you are never sure where the vessel will discharge as often it could get diverted to another port," the source said. "So the Iranians could charter a vessel FOB Singapore or China, and then it could sail directly to Iran."

WHAT EFFECT WILL FRESH SANCTIONS HAVE?

Iran will face more pressure and further trading difficulties, given that the United States and European Union are expected to pass fresh sanctions.

"The shipping lines will continue to find ways around it by creating new companies," IHS's Ciszuk said.

"All of this comes with an added cost, an extra time lag and extra layers of waste. This is starting to feed through to the whole economy and makes it very hard for smaller companies."

Shipping is vital for Iran's economy, and analysts say trade flows will depend on how vigorously countries choose to inspect ships suspected of carrying prohibited items.