MANILA (AP) - Philippine President Rodrigo Duterte ordered the military to prepare to deploy its aircraft and ships "at any moment's notice" to evacuate thousands of Filipino workers in Iraq and Iran, reflecting Asia's growing fears for its citizens amid a potential outbreak of violence in the Middle East.

Other Asian nations with large populations of expatriate labour may face similar decisions amid the rapidly escalating tensions between the United States and Iran following last week's US airstrike that killed Iran's Major General Qassem Soleimani in Baghdad.

South Korea's Foreign Ministry said last week it would work to increase the security of about 1,600 of its nationals in Iraq, where they work mostly in construction sites. India's foreign ministry spokesman Raveesh Kumar said India wasn't planning to evacuate any citizens from the volatile region "yet."

Mr Duterte held an emergency meeting with his defence secretary and top military and police officials Sunday (Jan 5) to discuss the evacuation plans.

"President Duterte ordered the Armed Forces of the Philippines to be prepared to deploy military assets to repatriate overseas Filipinos in the Middle East, particularly from Iran and Iraq, at any moment's notice," said Senator Christopher Lawrence Go, a close ally of Mr Duterte who was at the meeting.

Mr Duterte expressed fears Monday that the Philippines may have to carry out massive evacuations if violence hits Middle Eastern countries like Saudi Arabia that host large numbers of Filipino workers.

"I'm nervous. Iran seems to be hell-bent on a retaliation, which I think will come. It's a matter of time ... the cry for blood is there," Mr Duterte said in a speech.

He urged Congress to hold a special session on the impact of a possible crisis in the Middle East and set aside contingency funds.

Iran has vowed to retaliate and US President Donald Trump warned American forces would hit back at 52 Iranian targets if Americans come under attack.

Iraq's Parliament has also called for the expulsion of all American troops from Iraqi soil, which could revive the Islamic State of Iraq and Syria (ISIS) group in Iraq, making the Middle East a far more dangerous and unstable place.

Compounding contingency plans is the uncertainty where hostilities could possibly break out.

Military chief of staff Lieutenant General Felimon Santos Jr said Philippine forces have identified possible evacuation routes not only in Iraq and Iran but other hotspots, like Israel.

"There are probabilities like that and we are improving our plans just to cover everything just in case something happens," Lt Gen Santos told reporters in Manila.

There are more than 7,000 Filipino workers and their dependents in Iraq and Iran, including many who work in US and other foreign facilities and commercial establishments in Baghdad, the Department of National Defence said.

The workers in Iran and Iraq are a small fraction of the hundreds of thousands of Filipinos who are employed in countries lining the Persian Gulf.

The Philippines is a leading source of labour worldwide with about a tenth of its more than 100 million people working mostly as household help, construction workers, seamen and professionals.

Other countries face similar dilemmas. Asians make up 40 per cent of the world's migrants, and Middle Eastern countries are a common destination.

Gulf Arab states are home to more than 7 million Indian expatriates who help drive the region's economy and keep its cities teeming with doctors, engineers, teachers, drivers, construction workers and other labourers. In United Arab Emirates, Indians outnumber Emiratis three to one.

South Korea's Foreign Ministry said Monday that government agencies had discussed preparations for an escalating crisis in the Middle East but had no immediate plans for evacuations.

The ministry said about 1,600 South Koreans are in Iraq, mostly working in construction, while another 280 who live in Iran are business people, students or spouses of Iranians.

On past occasions, China has evacuated its citizens from other countries during times of conflict, political tension or natural disaster.

In 2015, the navy transported nearly 500 Chinese out of war-torn Yemen. It evacuated 3,000 from Vietnam in 2014, after the deployment of a Chinese oil rig in disputed waters elicited a wave of anti-China riots.