Iran has brought into service a new ballistic missile that is capable of hitting Israel.
Iran says its missiles are meant purely as a deterrent
Iran's supreme leader Ayatollah Ali Khamenei attended a televised ceremony to hand over to the armed forces the Shahab-3 missile which has a range of 1,300 kilometres (800 miles).
"Today our people and our armed forces are ready to defend their goals anywhere," Mr Khamenei was quoted as saying by the AFP news agency.
Israel and the United States - which both accuse Iran of trying to develop nuclear weapons - have expressed grave concerns over the latest developments.
Iran is also under growing pressure from the UN nuclear watchdog, the International Atomic Energy Agency, to sign the so-called additional protocol to the Nuclear Non-Proliferation Treaty, allowing tighter inspections of its nuclear facilities.
Iran has repeatedly denied the charges, insisting that its missile programme is purely meant as a deterrent.
'Ready to defend'
Iranian television showed Mr Khamenei, flanked by officers and other clerics, and three of the Shahab-3 rockets on what appeared to be mobile launchers.
"This divine force has answered all threats," Mr Khamenei was quoted as saying in front of about 1,000 troops in ceremonial dress.
Iranian television also reported that the Revolutionary Guards - who have their own air force - were given some new but unidentified attack and transport helicopters as well as an undisclosed number of Russian-built Sukhoi-25 jets.
The head of the Revolutionary Guards, Yahya Rahim-Safavi, was quoted as saying in his speech during the ceremony that his force was now "ready to defend Iran against any threat".
The surface-to-surface missile was first tested in 1998.
It was handed over to the armed forces after the final test was conducted earlier this month.
The Shahab-3 could also reach eastern Turkey and Pakistan.
In Farsi, Shahab means "meteor" or "shooting star".
Iran launched an arms development programme after its 1980-88 war with Iraq, following a US weapons embargo.
Since 1992, Iran has announced the production of missiles, a fighter plane, tanks and armoured personnel vehicles.