Iran launched a new long-range missile late last month, a general announced on Monday, trumpeting the accuracy of the latest such weapon to be test-fired in defiance of the West.

"A missile with a 2,000-kilometre range was tested two weeks ago," said General Ali Abdolahi, adding that it has a negligible margin of error of just eight metres (yards).

"We can guide this ballistic missile. It leaves the Earth's atmosphere, re-enters it and hits the target without error," the armed forces deputy chief-of-staff said, quoted by the website of state broadcaster IRINN.

However, several hours later, Defence Minister General Hossein Dehghan denied that such a test had taken place.

"We have not tested a missile with such a range as media reports said," he said, quoted by the official IRNA news agency.

In early March, Iran carried out several short-, medium- and long-range (300 to 2,000 kilometres) precision missile tests across its territory, mostly from underground bases.

The series of tests has come in for criticism from the United States, Britain, France and Germany.

They say the tests violate United Nations resolutions, and have called on the Security Council to address them.

Opponents of the programme say the weapons are capable of carrying nuclear warheads, an argument categorically denied by Tehran's political and military authorities.

Tehran's ballistic missile tests in late 2015 brought new sanctions by the US against Iran on January 17.

The punitive measures were announced a day after international sanctions were lifted following the entry into force of a July 2015 nuclear agreement.

Iran's parliament, whose mandate expires at the end of May, passed new legislation this month that boosts the country's ballistic capability.

President Hassan Rouhani and senior Iranian military officials have also said in recent months that ballistic missiles must be enhanced in order to boost Iran's deterrent power.