Iran May gasoline imports were expected to drop by about 20 per cent versus the previous month, as top independent traders and international oil firms cease sales to the Islamic republic, according to industry sources.

European energy giant, Total  of France, which continues to supply Tehran with gasoline was expected to ship up to 50 per cent of Iran total purchases for May, traders said.

Iran was expected to import around 102,300 barrels per day (bpd) of gasoline from the spot market this month, or about 12 cargoes, traders said.

'We could be slowly beginning to see the impact of the move by companies pulling back from Iran business because of the sanctions threat by the United States,' an Asian based gasoline trader said.

Last month, senior management at Russia's No.2 oil company, Lukoil, gave verbal direction instructing traders involved in gasoline sales to Iran to cease business activity with Tehran.

Malaysia's state oil company, which had been a key supplier of gasoline to Iran in the fourth-quarter of 2009, and the first few months of 2010, told Reuters it had ceased sales to the world's fifth-largest oil exporter.

US politicians are working on legislation to penalise fuel suppliers to Iran in an effort to pressure Tehran to stop uranium enrichment.

The West says the world's fifth-largest oil exporter is using its atomic programme to develop a nuclear bomb, while Iran insists it is for electricity.

Total's chief executive Christophe de Margerie said in April that if the US passed its legislation targeting companies selling the motor fuel to Iran, it would cease doing business with it.

Despite the sanctions Iran has maintained a robust import programme of gasoline from the international market. Last month state-run ChinaOil sold two gasoline cargoes to Iran, the first known direct sales to the Opec-member.

Previously sales from China were mostly done via third-party companies. Due to a chronic lack of refining capacity, Tehran has to import at least 30 per cent of its gasoline needs - making it vulnerable to any future sanctions that could interrupt that vital inflow.-Reuters