Canada's largest airline announced Monday it has suspended flights to and from Venezuela capital Caracas as violent protests continue in the country.

"Due to ongoing civil unrest in Venezuela, Air Canada can no longer ensure the safety of its operation and has suspended flights to Caracas until further notice," said the airline in a statement.

Air Canada said its last flight departed Caracas on Sunday, March 16.

Prior to the suspension, Air Canada operated three return flights per week between Toronto and Caracas. The airline said customers holding tickets for later flights will receive a refund.

"Air Canada will continue to monitor the situation and will evaluate the re-introduction of flights with the objective of resuming operations on the route once Air Canada is satisfied that the situation in Venezuela has stabilized," said the statement.

For more than a month demonstrators have been clashing with security forces in Venezuela, marking the biggest threat President Nicolas Maduro has faced since his election last year.

Violent protests have continued in Caracas for weeks.

Students and other anti-government protestors are unhappy with Venezuela's economy and rising crime.

Despite being one of the world's top 10 oil-producing countries, more than 25% of Venezuelans live below the poverty line. More than 20 people have been killed during the demonstrations, according to government figures.

MORE: Protests rage in Venezuela, one month on

IATA: Venezuela not playing by the rules

Air Canada's cancellation of its Caracas services comes amid a financial dispute between airlines and Venezuela's government.

International Air Transport Association's CEO Tony Tyler said in a speech March 12 that the Venezuelan government is stopping airlines from repatriating around $3.7 billion in earnings.

For several months, airlines have reportedly been unable to access money earned in ticket sales in Venezuela due to the company's tight currency controls. Ecuadorean flag carrier Tame suspended flights to Venezuela for three days in January over blocked payments.

"It is unacceptable that the Venezuelan government is not playing by the rules to which it is treaty bound," said Tyler.

"The impact of this blocked cash is quite easily seen when you consider that airlines this year will only make $18.7 billion globally. Of course this is cash and not pure profit.

"Airlines certainly cannot sustain operations indefinitely if they can't get paid. I have written to President Maduro asking for his urgent attention to this issue."

According to a report by Venezuela's Spanish-language daily el Nacional, Maduro told reporters on March 14 that any airline that pulls its operations from the country will not be allowed to return while he's in power.