Iran's navy began a 10-day drill on Saturday in international waters near the strategic oil route that passes through the Strait of Hormuz.

The exercises, dubbed "Velayat 90", could bring Iranian ships into proximity with US navy vessels in the area.

The exercise covers a 2,000-kilometer stretch of sea off the Strait of Hormuz, northern parts of the Indian Ocean and into the Gulf of Aden, near the entrance to the Red Sea, state TV reported.

Different classes of submarines, the latest ground-to-sea missile systems and torpedoes will be employed in the maneuvers.

The drill will be Iran's latest demonstration of strength in the face of Western criticism over its nuclear program, which Teheran insists is for peaceful purposes only.

It is the first time that Iran's navy has conducted drills over such a vast area, Iranian Navy Commander Rear Admiral Habibollah Sayyari said at a press conference on Thursday.

"To show off its might, the navy needs to be present in international waters. It's necessary to demonstrate the navy's defense capabilities," state TV quoted Sayyari as saying.

Sayyari rejected reports about a possible one-day closure of the Strait of Hormuz during the exercise, adding that Iranian forces are capable of accomplishing such a feat, but such a decision must be made by the nation's leaders.

The Strait of Hormuz is of strategic significance as about one-third of the world's oil tanker traffic passes through it. Beyond it lie vast bodies of water, including the Arabian Sea and the Gulf of Aden.

The US Navy's Bahrain-based Fifth Fleet is also active in the area, as are warships of several other countries taking part in anti-piracy operations.

Both the United States and Israel have not ruled out a military option against Iran over its nuclear program.

Some political figures in Iran have warned that the country could seal off the key waterway if the US or Israel moved against Teheran's nuclear facilities.

Iran's latest drill is a gesture in response to recent diplomatic and military threats by the US and Israel, said Hua Liming, a former ambassador in the Middle East and a researcher at the China Institute of International Studies.

"From a military perspective, the move will not have much impact on the US, since the military strengths of the two countries are asymmetric," said Hua.

"But Iran wants to demonstrate that it has the ability to take revenge, and is capable of attacking the US Fifth Fleet and its troops in Afghanistan."

Hua said that although Iran can easily block the Strait of Hormuz, which is only 54 km wide at its narrowest point, with underwater mines and torpedo boats, the country will not make the move rashly.

"If Iran closes the strait, a major passageway of oil shipments in the world, it will also have negative effects on Teheran," said Hua.

"Therefore, the country will not block the strait, unless it is out of absolute necessity. Now, the closure of the strait remains a threat."