Lufthansa cancels almost half of flights due to pilots' strike

German flagship carrier Lufthansa cancelled 1,350 flights, or 48 percent of scheduled services, for Monday and Tuesday as its pilots prepared to go on strike.

The cancellations will affect more than 150,000 passengers, Lufthansa said in an e-mailed statement, which adds to pressure from a stuttering global economy and increased competition.

Lufthansa planes
Boris Roessler | AFP | Getty Images
Lufthansa planes

German pilots' union VC had called a two-day strike at the carrier, starting midday on Monday, after talks broke down over retirement benefits late last week.

The dispute over proposed changes to an early retirement scheme for pilots that was developed decades ago has already resulted in eight separate strikes this year, wiping 160 million euros ($199 million) off the carrier's operating profit.

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Lufthansa, which last month lowered its profit guidance for 2015 for the second time this year, is expanding low-cost operations to better compete with budget carriers and Gulf rivals and to outflank the pilots' union.

Shares in Lufthansa fell 4.6 percent in pre-market trade at brokerage Lang & Schwarz on Monday, while the German blue-chip DAX index .GDAXI was seen down 0.6 percent lower.

Read MoreLufthansa cuts 2015 outlook again

The union has said the Germany-wide strike is to last from midday (1100 GMT) on Monday to 11:59 pm (2259 GMT) on Tuesday for short- and medium-haul flights, as well as from 3 a.m. (0200 GMT) to 11:59 pm (2259 GMT) on Tuesday for long-haul flights.

Pilots flying for Lufthansa Cargo will also strike from 3 a.m. to 11.59 pm on Tuesday. Flights of budget arm Germanwings will not be affected.