The federal government has been urging Canadians in Libya to leave without delay amid escalating violence, but a string of problems has impeded its evacuation efforts.

On Thursday, a plane charted by Ottawa to help retrieve Canadians was stranded in Italy due to insurance problems. When a second chartered plane took off from Amman, Jordan, and managed to land in the North African country overnight Thursday, it returned without any passengers.

Then on Friday an advisory from Foreign Affairs warned Canadians against travelling to the Tripoli airport even though another plane was on the way. Meanwhile, a large C-17 military aircraft sent to fetch Canadian citizens remains grounded in Italy awaiting permission to land on Libyan territory.

Late Friday night, the advisory was updated to say that Canadians should wait until dawn to travel to the Tripoli airport, Foreign Affairs said.

An official told CTV's Middle East Bureau Chief Martin Seemungal that the chartered plane from Jordan made a second trip to Tripoli by Friday night and circled the airport for two hours, unable to land due to "major problems" on the ground.

While a Foreign Affairs spokesperson told The Canadian Press that the embassy in Tripoli remained open for emergency consular services, many Canadians were reportedly making their own way out of the country.

Some flew out on planes chartered by other countries or on board a ferry hired by Washington, for example. But when foreigners turned to the sea to leave, strong winds delayed ships from leaving port.

Seemungal said that getting into Libya and getting people back out again "is not an easy situation," and that other governments have been facing similar problems.

"It's pretty much across the board. The Americans, for example, tried to get a plane in a few days ago and were refused entry outright," he reported from Rome.

Defence Minister Peter MacKay said that confusion in Tripoli had caused the chartered plane to leave empty.

"That has to do with co-ordination on the ground, ensuring that people are aware that an exit is available to them," MacKay said. "We're trying to co-ordinate that through the Department of Foreign Affairs and through other countries."

Ottawa is increasingly concerned about the threats to its citizens and is insisting that "every Canadian must get out of Libya immediately," CTV's Ottawa Bureau Chief Robert Fife said.

At least 213 of the 344 Canadians registered with the embassy in Tripoli have told Foreign Affairs that they want to leave the country.

Fife said at least 200 Canadians had fled by Friday afternoon but as many as 700 others may remain within Libya's borders, many of whom have not registered with the embassy.

Departures from Tripoli, Benghazi

Despite the travel difficulties, a group of 15 Canadians boarded a United Kingdom-bound flight in Tripoli on Friday.

Three other Canadians arrived at the airport too late to make the flight, but Fife said that Canadian officials were arranging a flight to Malta for them.

A number of other Canadians also left Libya via a British ship that departed from the eastern city of Benghazi on Friday, Fife said.

Gar Pardy, the former director-general of consular affairs in Ottawa, said that Canada will continue to rely on help from other countries -- and they will expect help in return.

"It's a joint international operation, so we share seats with them and they share seats with us," Pardy told CTV's Canada during an interview from Ottawa on Friday morning.

Fife said that Canadian officials will be carrying small Canadian flags with them at the Tripoli airport to make themselves more visible to citizens.

"When you see that flag, get over there," Fife said. "Those are Canadian officials who are going to make sure that you get out of Tripoli."

Growing dangers

Seemungal said it is possible that some Canadians simply could not travel to the airport on Friday because of the dangers they would face en route.

"Essentially the situation between the city and the airport is extremely volatile, it changes all the time," he told CTV News Channel in a telephone interview. "You have these Gadhafi loyalists manning these checkpoints and demanding either money or threatening people, and so it's not exactly a safe situation."

Any Canadians stranded in Libya who need emergency consular assistance or who want to leave the country can call the embassy in Tripoli at 218 (21) 335-1633. They can also call the emergency operations centre in Ottawa at 613-996-8885, or send an email to sos@international.gc.ca.

Family and friends seeking information about loved ones in Libya can call the emergency operations centre at 1-800-387-3124. They can also send an email to sos@international.gc.ca.

With files from The Associated Press and The Canadian Press