Ali Larijani, asked to confirm reports that Iran had bought 29 mobile air defence systems from Moscow in a contract worth more than $700 million, said: "Is this a problem? Do we need permission?
"We have contracts with other countries to buy or sell arms. This is not the first time we have signed a contract with the Russians. We have done so in the past with Russia and other countries like China.
"This is not the first time we have bought an anti-missile system. We also make them ourselves."
Larijani said that "long-range missiles do not only have a military use, because to launch satellites you need long-range missiles".
"We always announce the range of missiles we test. There is nothing secret," he said.
Russia's state news agency, ITAR-TASS, on Friday quoted an unnamed top Russian Defence Ministry official as saying the deal involved 29 Tor M-1 mobile systems capable of bringing down aircraft and missiles.
Iran growing impatient
"We always announce the range of missiles we test. There is nothing secret"
secretary of Iran's Supreme National Security Council
Larijani also indicated that Iran was impatient to resume nuclear enrichment work. This provides reactor fuel but is also a step in weapons production. He said this step could come "within a few months".
"This is not up for negotiation, and the when and hows of a resumption concern us alone," Larijani said. "In our universities, we are conducting research.
"Does making centrifuges or conducting research mean you can make a bomb? No. You need to inject gas into them for this," he said, adding that Iran is "ready to give guarantees" that it will not make weapons-grade uranium.
Japan atomic bombs
"Iran does not want to make an atomic bomb. And those who dropped an atomic bomb on Japan are in no position to forbid us from having (civilian) nuclear technology," Larijani said in the interview.
"We will welcome any proposal that keeps to the following condition: enrichment must take place in Iran, because this is a right."
Britain, France and Germany, backed by the US, say that the only guarantee that Iran will not use its nuclear programme to acquire the bomb is for it to abandon uranium enrichment activities.
Larijani said that expert-level talks between the two sides aimed at exploring avenues for resuming negotiations, which had broken down in August, "will take place in two or three weeks".
The EU countries want to raise a proposal from Moscow under which Iran's uranium would be enriched only in Russia.
Larijani has said Iran, which has already spurned a "Libya-style deal" involving trade and diplomatic incentives, will not accept the kind of accord the West is now hoping for. "The negotiations will be about making nuclear fuel inside Iran," he said. "There is nothing else to talk about.
"We are a member of the International Atomic Energy Agency and accept the Non-Proliferation Treaty. We have commitments, which we meet, as well as rights: so there is no need to set discriminatory rules for us."
Larjani said those who bombed
Japan should not restrict Iran
Iran has already ended a freeze on uranium conversion, which makes the gas fed into centrifuges in the enrichment process.
"High oil prices have a dissuasive effect. Iran is a difficult target, whereas Iraq was weakened by eight years of war and the attack on it after it invaded Kuwait. The Iraqi government had a problem of legitimacy ... and this is not the case for Iran," he said.
An attack against Iran would be "a risk that no intelligent person or logical country would take", he said, and the US "is bogged down in Iraq".
As for a potential missile strike against Iran, he said its air defences "do not have many weaknesses".