German airline Lufthansa has cancelled the majority of its flights scheduled for Monday due to a strike.The airline said about only about 30 of its flights would run as planned on Monday, out of more than 1,700 originally scheduled.Ground staff have called a one-day strike in a pay dispute.Last week Lufthansa rejected union demands for a 5.2% wage increase over the next 12 months.Strikers are also looking for guarantees over job cuts.Like many airlines, Lufthansa is looking to cut costs in the face of stiff competition from low-cost carriers and big Gulf airlines, as well as rising fuel prices.Unions staged a similar one-day strike last month. Short "warning strikes" are a common tactic among German unions, designed to put pressure on wage negotiations.In a statement on its website, Lufthansa said passengers should expect "massive" flight cancellations and delays that will start to affect long-haul flights from Sunday.