Here is an article off rense.com
http://www.guardian.co.uk/world/2008/sep/17/iran.usa
in which it states:
'This week the US Congress is debating two non-binding resolutions which, if passed, will greatly increase the likelihood of military intervention against Iran. They call on the US president to "increase economic, political and diplomatic pressure on Iran to verifiably suspend its nuclear enrichment activities", and demand "stringent inspection requirements" of all goods entering or leaving Iran and an embargo of refined petroleum products to Iran. Although both resolutions exclude authorisation for military action, the embargo 
will require a naval blockade. Such a blockade could result in skirmishes with the Iranian navy which could rapidly escalate.
The US is massing the largest armada of warships in the Gulf since 2003.'
(my emphasis)