Iran has achieved breakthroughs in nuclear and space technology despite international sanctions against it, the country's top leader said Saturday.

Ayatollah Ali Khamenei told military commanders that instead of weakening Iran, sanctions by the U.S., the U.N. and others have forced it to become more self-reliant, leading to greater strides by Iranian scientists and to technological advancements unseen in the country's history.

Iranian leaders often boast of technological advancements as they seek to assure their people that sanctions and isolation have not hurt the country, even as unemployment and inflation increase.

Most recently, President Mahmoud Ahmadinejad announced on Tuesday the launch of Iran's first domestically produced satellite. He faces a tough re-election battle this year, not least because of the economic woes brought on by falling oil prices and sanctions.

The United States imposed sanctions against Iran soon after its 1979 Islamic revolution, which toppled the U.S.-backed Shah Mohammad Reza Pahlavi and brought hard-line clerics to power. The sanctions banned the export of any dual-use technology, including nuclear, space and missile equipment. Over the years, Washington has tightened sanctions against any investment in Iran.

Since 2006, Iran has also been under U.N. Security Council sanctions, applied to its nuclear and missile industries, for refusing to halt uranium enrichment, a technology that can be used to produce fuel for nuclear power plants or the material for atomic bombs.

The United States and some of its allies have accused Iran of seeking to build nuclear weapons. Iran has denied the charge, saying its nuclear program is geared towards generating electricity, not weapons production.

Iran says it has achieved proficiency in the entire nuclear fuel cycle — from extracting uranium ore to enriching it — and says it has 5,000 centrifuges operating in its Natanz uranium enrichment plant in central Iran.

On Monday night, Iran sent its first domestically made satellite — called the Omid, or hope in Farsi — into orbit using an Iranian-built satellite-carrier rocket. Analysts described it as a key step for an ambitious space program that worries the U.S. and other world powers because the same rocket technology used to launch satellites can also deliver warheads.

"It was from the depth of various kinds of sanctions imposed on Iran for years that the Omid satellite came into existence and was sent into orbit," state television quoted Khamenei as saying.

"And it was out of all restrictions imposed against the Iranian nation that (Iran) achieved uranium enrichment technology, which is in the hands of few powerful countries," Khamenei was quoted by the television as saying.

Among Iran's other scientific boasts, it says it cloned a sheep in 2006. Iran has also built small passenger planes, though it lacks spare parts for its fleet of bigger U.S.- and European-made commercial aircraft. It also exports luxury cars.

Iranian political analyst Saeed Leylaz said Iran's defense industry has also made strides despite international sanctions.

Prior to the revolution, "Iran was a net importer of weapons," Leylaz said. "Sanctions forced Iran to produce its defense requirements domestically. Now, it's even an exporter of weapons."

In July 2003, the Revolutionary Guards were equipped with the Shahab, or Shooting Star, a medium-range missile that can carry a nuclear warhead and reach Israel and various U.S. military bases in the region. Since then, it has tested several missiles with a range of 1,240 miles.

Iran says it has developed solid fuel technology in producing missiles, a major breakthrough that increases accuracy.