An Air Canada spokesperson said the airline has resumed its full array of flights to London's Heathrow airport Tuesday evening.

This will mean a return to the regular schedule of nine flights going to London and nine returning to Canada on Wednesday, Peter Fitzpatrick told CTV News.

"We think it's good news, but at the same time, there's quite a backlog of passengers," he said. "We're not sure how long it's going to take to move all the people affected by cancelled flights, but it may well take a week or more."

It's difficult to put a number on how many people are affected, he said. Only about one-third of Air Canada's scheduled flights to Heathrow have been able to occur since the airport received about 13 centimetres of snow Saturday.

Holiday-season flights are almost always heavily booked, "but this is certainly going to alleviate the pressure," Fitzpatrick said.

Some British Airways flights also began to get back on track Tuesday, but the company warned it could take until Thursday for planes to begin taking off regularly.

In the meantime, U.K.-bound passengers at Pearson International Airport can only grit their teeth and wait.

Dennis Leslie is one of those feeling the frustration. The father of three from Brandon, Man., is spending his fourth day waiting for a flight to London to join his wife and children.

"You can put your name down on standby but, it's already overbooked," he said Tuesday.

"Every time you don't get your name called, you've got to go stand back in line. You get your name put to the bottom of their priority list, so then you wait again. They only take 10 people … flight get cancelled, back in line, put your name on a list."

Sarah Newberry said she was supposed to be on priority standby "because I'm running out of my medication, and there's no communication between staff, and I'm left again."

One woman said she knows she won't return to Britain in time for Christmas, with her flight booked for Dec. 29.

Another British citizen said if he could just get home for Christmas, all the hassles would be worthwhile.

One flight departed Pearson on Tuesday for Heathrow at 8:30 a.m.

Flights taking off from Pearson Tuesday night:

  • AC848
  • AC856
  • AC868

People should check their flight's status before heading to the airport, Fitzpatrick said. Stranded passengers should either rebook online or through a call centre, but there are long delays through the call centre, he said.

British Prime Minister David Cameron had offered the services of the army to get Heathrow fully operational as soon as possible, but the airport declined.

For much of Tuesday, only one runway was available, with more than half of Heathrow's flights being cancelled. But a second runway has since re-opened. Nine flights are set to land in Canada from Heathrow Wednesday morning.

Europe's top transport official has threatened tougher regulation for airports for not being able to handle the winter weather.

With a report from CTV Toronto's Janice Golding