DUBAI, Jan 25 (Reuters) -

Iran staged war games on Friday involving newly developed rapid redeployment units focused on fighting enemy aggressors and armed militants, state media reported, amid increased tensions with the United States and following a militant attack.

Around 12,000 elite troops, armored vehicles, fighter jets and drones were taking part in the two-day exercises, staged in the central province of Isfahan, state television said.

Deployed by transport planes and 60 helicopters, commandos hunted mock armed militants, while an armored battalion blocked "enemy" forces trying to retreat, state media said.

"In these war-games we will showcase two important developments: a special-forces rapid deployment battalion and a highly mobile offensive armored battalion," General Kioumars Heydari, head of the regular army's ground forces, told state television.

Heydari said the war games would delight Iran's friends and show any aggressors that they would face a "rapid and crushing blow" by the Iranian army, the state news agency IRNA reported.

Relations between Iran and the United States, always frosty, have deteriorated further following President Donald Trump's decision to pull out of an international accord curbing Tehran's nuclear program and to reimpose economic sanctions on Iran.

Tensions have also risen between Iran and arch-enemy Israel as well as its Gulf neighbors, especially Saudi Arabia, while last September Islamic State claimed responsibility for an attack on a military parade in which 25 people were killed.

Iran holds military exercises several times a year to demonstrate its readiness to respond to any foreign aggression.

Western defense analysts say Iran often exaggerates its military strength.