Iran has warned the UN's atomic agency not to refer it to the Security Council over its nuclear programme.
A referral could lead to UN sanctions against the Islamic republic.
Tehran hinted that such a move could prompt it to start uranium enrichment as well as a uranium conversion process that has already been resumed.
The remarks came after the UK foreign secretary described as "unhelpful" an assertion by Iran's president that Iran had a right to produce nuclear energy.
The US and the EU want Iran to give up any idea of enrichment capability.
Tehran recently resumed uranium processing, an activity that had been suspended since November 2004 while talks were held with three European countries - the UK, France and Germany - about its long-term nuclear plans.
Western powers fear Iran secretly wants to develop the ability to make a nuclear bomb.
The board of governors of the UN's nuclear agency (IAEA) is meeting on Monday in Vienna.
'No use bullying'
But Iranian foreign ministry spokesman Hamid Reza Asefi said a political decision by the board would further complicate matters.
"Enrichment is not on the agenda for the time being but if the IAEA meeting on Monday leads to radical results, we will make our decision to correspond to that," he said.
"The Islamic Republic of Iran is deaf to the language of threats," he added.
"We hope that they follow the path of logic so the case returns to a normal path. The language of bullying has never had any use in the past."
On Saturday Iranian President Mahmoud Ahmadinejad told the UN his country had an "inalienable right" to produce nuclear energy - but said Islam precluded Iran having atomic weapons.
He said Iran's programme was entirely legal and attacked what he called a "nuclear apartheid" that permits some countries to enrich fuel, but not others.
UK Foreign Secretary Jack Straw said the speech was "disappointing", given recent talks with Iran over its nuclear stance.
"It is a difficult moment for the international community," he added.
An EU spokeswoman told Reuters news agency Mr Ahmadinejad's language "leaves us no alternative but to pursue a UN referral".
"However, we want to build an international consensus on the matter. So we will be consulting with everybody," she said.
French Foreign Minister Philippe Douste-Blazy said the option of reporting Iran to the Security Council to face possible sanctions "remains on the agenda."
But BBC diplomatic correspondent Bridget Kendall said it was not certain whether the US and EU partners would convince other countries that Iran deserved to be reprimanded.
Iran has invited other nations to collaborate on its nuclear activities, which may for some sound like an attractive offer, she says.
Iran's complaint that there is a double standard about who is allowed to become a nuclear power may be met with some sympathy, our correspondent adds.