Egypt's President Abdel-Fattah El-Sisi has convened a meeting to draw up an evacuation plan for Egyptians in Libya, hours after Egypt conducted airstrikes on Islamic State positions in the country.

On Sunday, the militant Islamic State group published a video purpotely showing its execution of 21 Egyptian Coptic Christians in Libya. Egypt responded with airstrikes in Libya early on Monday, sparking fears of reprisals against Egyptian expatriates in the country.

The meeting will include plans for necessary communications with Libyan tribes and international organisations to secure the evacuation of Egyptians there, sources at the presidency told Ahram Online.

Hundreds of thousands of Egyptians are believed to still be present in Egypt's neighbouring country. The International Organisation for Migration estimates that 330,000 to 1.5 million Egyptians worked in Libya until Muammar Gaddafi was toppled in 2011, sending millions of dollars back to Egypt in remittances.

The sources said airstrikes may be used to facilitate the evacuations, especially for those who cannot reach the Tunisian borders. 

Egypt's Civil Aviation Minister Hossam Kamel told the Aswat Masriya news website that Egypt's national carrier Egypt Air is ready to execute evacuation plans as soon as orders are received, confirming an evacuation plan is in order.

Kamel said planes will land in Tunisia due to current difficulties of landing in Libyan territory.

He said four Tunisian airports will be used to airlift the fleeing Egyptians.

Fajr Libya, the armed group that controls the capital Tripoli, has called on Egyptian workers in Libya to leave Libyan lands within 48 hours for their own safety.

Fajr Libya said in their statement that their call "will protect Egyptian workers from any revenge attacks on them, which would only create a dispute between two brotherly peoples."

El-Sisi said late on Sunday, after the publication of the execution video, that tighter measures would be implemented to prevent Egyptians from travelling to the beleaguered country. 

Flights from Egypt to Tripoli stopped last summer due to increasing violence between warring Libyan factions, the worst since the overthrow of Gaddafi in 2011.

Egypt sent several evacuation flights to Tunisia in July and August, carrying thousands back to the country.

An internationally-recognised government led by Abduallah El-Thinni resides in the eastern city of Tobruk. 

El-Thinni's Cabinet, however, is contested by another Islamist-led government headed by Omar El-Hassi and headquartered in the capital Tripoli.

A coalition of Islamist-led militias calling itself Fajr Libya (Libya's Dawn) has controlled Tripoli and a number of western areas since August 2014.

Meanwhile, IS in Libya, which formed in the last two years, maintains control of different patches of the country.