MADRID, Jan 5 — Ground staff at IAG-owned Iberia airlines today began a four-day strike at Spanish airports, forcing the cancellation of hundreds of flights, but the airline reported minimum impact on services.

Iberia in a statement said that as of 7am local time operations were beginning normally and only 17 per cent of those involved were taking part in the strike.

With the strike trailed for weeks amid discussions between the company and unions, "more than 90 per cent of customers have already obtained a solution to the cancellation of their flight,” Iberia said earlier.

Ground staff including baggage handlers are protesting against contracts signed with new providers at Spanish airports after talks between unions and the company failed at a last-ditch meeting.

Spain’s two main unions UGT and CCOO have called for strike running from January 5 until January 8, disrupting travel over the country’s traditional Epiphany holiday.

Neither union had announced participation figures as of early today.

An Iberia press official said on late yesterday that Madrid airport would not be affected, but airports likely to be affected included Alicante, Barcelona, Bilbao, Gran Canaria, Ibiza, Malaga, Palma de Mallorca and Tenerife.

Iberia, Iberia Express and Air Nostrum had cancelled 400 flights and other IAG partner airlines an additional 300, she added.

Other airlines that use Iberia Airport Services could be affected, she added, though minimum service legislation meant disruption should be limited.

She noted only 3,800 of its 8,000 ground service workers worked at airports where services were now being run by new contractors and it remained unclear how widely the strike would be observed.

Paloma Gallardo, the Iberia representative for union CCOO, said earlier that the union expected the strike to be observed at all airports, including Madrid.

"We hope it will be as much as possible,” she said. "The conflict is very serious.”

Spanish commercial airports are operated by state-controlled Aena, which in September hired new contractors for services that were previously provided by Iberia in many airports, angering unions even though the new suppliers committed to retain workers and their working conditions.

Iberia is challenging the new contracts in the Spanish courts and has called strike action in the meantime "irresponsible”. — Reuters