BERLIN: Iran's Revolutionary Guards chief has drafted a plan to cause an environmental disaster in the Strait of Hormuz to block seaborne oil exports with the goal of removing economic sanctions imposed on Tehran, the weekly Der Spiegel said in an unsourced report.

There was no independent confirmation of the report.

The German newsmagazine reported that Mohammad Ali Jafari's plan, codenamed "Muddy Water", envisages the Iranians steering a tanker onto the rocks in the Strait, the world's most important oil shipping waterway.

"The aim is to block shipping temporarily through the contamination, to 'punish' adjacent Arab states that are hostile to Iran and to force the West to take part in a large-scale cleanup of the waters - and possibly thereby a suspension of sanctions against Tehran," Spiegel said.

"A decontamination would only be possible with technical help from the Iranian authorities and for this the embargo would have to be at least temporarily lifted," it said.

"Iranian firms, some of them owned by the Revolutionary Guards, could even profit from the rescue operations."

Der Spiegel gave no source for its report but said Western intelligence services were studying the plan, which it said now required only the approval of Iranian Supreme Leader Ayatollah Ali Khamenei to be put into effect.

Iran's economy is buckling under the weight of Western sanctions aimed at forcing the country to suspend its nuclear programme and negotiate seriously to resolve concerns that it is covertly trying to develop atom bombs, a charge Iran denies.

About 40 percent of the world's seaborne oil exports pass out of the Gulf via the Strait of Hormuz. Iran has previously threatened to disrupt Gulf oil shipping if Israel or the United States carries out any attacks on its nuclear facilities.