Iran concluded a major, three-day military exercise Friday intended to review the readiness of its armed forces. The drills, called "Great Prophet," also field-tested new military technology, including the Iranian-made Karrar tank and the Hamasseh drone, Middle East Monitor reported. The Iranian air force, elite units and local forces were involved in the exercise.

The drills covered four provinces in Iran’s southeast region near the border with Pakistan. The exercises came amid growing tensions in the area over the protracted civil war in Syria and the threat posed by the Islamic State group, also known as ISIS. Iranian forces are fighting alongside the embattled Syrian leader, Bashar Assad, in a move to strengthen the key Syrian ally.

Amid widening military involvement in the region, Iranian Major General Qassem Soleimani flew to Moscow Friday to meet with Russian military and political leadership, Reuters reported. He was expected to speak about military cooperation and the planned sale of S-300 missiles. Russia is also an important ally to Assad.

Soleimani has been subjected to an international travel ban and asset freeze since 2007, per a United Nations Security Council vote. The U.S. considers the Quds Force — the unit of Iran’s military led by Soleimani — a supporter of terrorism. States that are members of the U.N., including Russia, are not allowed to permit entry to blacklisted individuals.

U.S. allies in the Middle East, particularly Israel, have expressed concern over Iran’s strengthening military influence in recent months. Earlier this week, U.S. lawmakers pushed to boost aid for Israel’s missile defense technology, citing a purported Iranian threat.

Tehran saw crippling sanctions lifted early this year, per a landmark agreement signed between the U.S., Iran and five other world powers last summer. The controversial agreement, which was bitterly contested by Israeli leaders, requires Iran to place restrictions on its nuclear program.

Last month, the country allegedly carried out tests of two ballistic missiles. They were purportedly designed to reach Israel, a semi-official Iranian news agency said.