Iran's hardline rulers sent uncompromising signals to foes at home and abroad on yesterday, warning of possible legal action against opposition leaders and testing an upgraded missile that could reach Israel.
The United States said the launch of a Sejil 2 missile, with a reported range that would put the Jewish state and US Gulf bases within reach, undermined Iran's insistence of peaceful intentions and would be looked upon seriously by the world.
British Prime Minister Gordon Brown said it boosted the case for tougher sanctions over the major oil producer's disputed nuclear programme, which the West fears is aimed at making bombs. Tehran says it only seeks to generate electricity.
"This is a matter of serious concern to the international community and it does make the case for us moving further on sanctions," Mr Brown said in Copenhagen.
A senior Iranian energy official dismissed the latest effort to tighten the screw, saying a move by US lawmakers to target the Middle Eastern state with fuel sanctions would not cause any problems because Tehran had many gasoline suppliers.
Iran is the world's fifth-largest oil exporter but lacks enough refining capacity to meet domestic fuel needs, forcing it to import up to 40 per cent of its gasoline consumption.
This makes it potentially vulnerable to punitive measures that target the trade, although Iranian officials have repeatedly shrugged off the impact of such steps.
Yesterday's test of a Sejil missile, which Iranian Defence Minister Ahmad Vahidi said could not be destroyed by anti-missile systems due to its high velocity and anti-radar capabilities, drew swift Western condemnation.
"Such actions will increase the seriousness and resolve of the international community to hold Iran accountable for its continued defiance of its international obligations on its nuclear program," White House spokesman Mike Hammer said.
Mr Vahidi said the test of the Sejil 2 was aimed at boosting deterrent capabilities and posed no threat to the region.
Iran earlier this year said Sejil 2 had a range of 2,000 km (1,250 miles), enabling it to reach Israel and US bases in the region. Neither Israel nor the United States has ruled out military action if diplomacy fails to resolve the nuclear dispute. Iran has vowed to retaliate for any attack. On Tuesday, the US House of Representatives backed legislation to impose sanctions on foreign companies that help to supply fuel to Iran, a measure lawmakers hope would deter Tehran from pursuing its sensitive atomic activities.
"They cannot succeed," said Hojjatollah Ghanimifard, vice-president of investment affairs at the National Iranian Oil Company. "We have a long list of suppliers of gasoline."
Analysts say political turmoil in Iran since a disputed presidential election in June has further clouded prospects for any resolution of the nuclear dispute.
Internal tension has increased again since student backers of opposition leader Mirhossein Mousavi clashed in Tehran last week with security forces armed with batons and tear gas in the largest such anti-government demonstration in months.