The main airport in the capital Khartoum has been the site of heavy clashes, effectively shutting its operations. Fighting elsewhere has forced delays to some planned rescue operations.

Many countries unable to send forces into Sudan relied on others to extract their citizens via ports and military bases, with Saudi Arabia and France both evacuating numerous foreigners.

Some evacuations are taking place from Port Sudan on the Red Sea, an 850-kilometre (530-mile) drive from Khartoum, and others via nearby Djibouti and neighbouring Egypt.

A UN convoy carrying 700 people completed on Monday the arduous trip to Port Sudan.

Here is an overview of what various nations have done in efforts to take stranded citizens to safety.

- Arab nations -

Saudi Arabia led the first reported successful evacuations on Saturday, with naval operations picking up more than 150 people, including nationals from other countries.

Egypt's military last week evacuated 177 soldiers, and on Sunday the foreign ministry said 436 citizens had left by land. More than 10,000 Egyptians are thought to live in Sudan.

Over 200 Moroccans were taken to Port Sudan in convoys organised by their embassy, Rabat said Monday, adding that they would be flown home from there.

Both Tunisia and Algeria have announced rescue operations.

Jordan -- whose military airports have been used for some rescue flights -- said Saturday it had begun the evacuation of around 300 citizens with Saudi and UAE cooperation, while 52 Lebanese and 105 Libyans had also left on a Saudi naval vessel.

- US and Canada -

On Sunday, the US military sent three Chinook helicopters to evacuate American embassy staff from Khartoum, staying on the ground for less than an hour and extracting just under 100 people.

US officials have warned any wider effort to evacuate other Americans who remain is unlikely in the coming days.

But on Monday the Pentagon said it is providing intelligence, surveillance and reconnaissance capabilities to help the State Department identify potential land routes out of the country.

It has also positioned a destroyer off the coast of Port Sudan in case it is needed to transport American citizens or provide medical care.

Canada has pulled its embassy staff out, Prime Minister Justin Trudeau said.

- Britain, Norway, Switzerland -

The British military has evacuated embassy staff. Some British citizens still trapped in Sudan complained they felt abandoned.

The Norwegian ambassador said he and other Norwegian diplomats had also been evacuated, while Switzerland said 12 citizens had left with the help of other countries.

- European Union nations -

European Union foreign policy chief Josep Borrell said Monday that 1,000 EU citizens had been evacuated.

France has airlifted 400 people of multiple nationalities to Djibouti.

Amsterdam said it had sent two planes to fly out its nationals to Jordan.

Italy evacuated around 200 people in a military operation Sunday, rescuing all Italian citizens who "had asked to leave" and others including Vatican representatives.

Berlin said Monday three flights had left and a fourth was on its way to airlift a total of 400 people including other nationalities.

Austria, Romania, Hungary and Bulgaria said their citizens have been evacuated with foreign assistance. Around 65 people from those countries -- nearly half of them Austrian -- were still awaiting rescue.

A Spanish military plane with 100 passengers, 30 of them Spanish, left Sunday for Djibouti, Madrid said.

Finland said Monday it had evacuated 10 people so far.

- Turkey -

Ankara began operations on Sunday, taking some of its estimated 600 nationals by road from Khartoum and the city of Wad Madani.

But plans were postponed from one site in Khartoum after "explosions" near a mosque designated as the assembly area, the embassy said.

- African nations -

Chad said it was sending planes to collect 438 citizens who are leaving Khartoum by bus for Port Sudan.

Mauritania said 101 citizens also reached Port Sudan before heading on a Saudi naval vessel to Jeddah.

Uganda has evacuated more than 200 of its nationals on buses via Ethiopia, its ambassador told AFP.

Ivory Coast said 47 of its citizens were headed by bus from Khartoum to Cairo.

Nigeria plans to get nearly 3,000 of its nationals, mostly students, out by convoy to Egypt this week, a top official said Monday.

South Africa has begun evacuating dozens of its citizens including embassy staff "to a neighbouring country for safety", foreign affairs spokesman Clayson Monyela told AFP.

- Asia -

China said Monday it had "safely evacuated" a first group of citizens, with the foreign ministry estimating about 1,500 "Chinese compatriots" are in Sudan.

Delhi said on Monday "about 500 Indians have reached Port Sudan. More on their way."

A plane carrying 28 South Koreans including diplomats arrived in Jeddah on Monday, a Saudi official said.

Indonesia had moved 538 nationals from Khartoum to Port Sudan, with another group of 289 due to travel in a second phase.

The Philippines said Monday it would begin evacuating nearly 700 Filipinos "within the next 24 hours" on buses to Egypt.

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