Varig, Brazil's largest carrier, has said it plans to increase fares by the full amount.

But with the summer travel season under way, airlines are finding resistance to efforts to increase fares.

For the last year or so, they have been able to readily increase fares, in part because of the strong economy.

The only way to offset that shortfall, transit officials say, is to increase fares and reduce services.

Bankrupt airlines are always looking for ways to increase their cash flow and offer lower fares.

The bus system has not increased fares since 1995.

The Government plans to increase fares by three per cent above inflation in 2013 and 2014.

The regulators said the terms of the bid would reduce flights and increase fares between the nations.

This puts the industry into a better position to increase fares because there are few excess seats.

The third option, transit officials said, would increase fares and tolls but offer the same level of discounts available now.