Oslo  - A strike by Norwegian civil aviation employees expanded Monday to partly impact Oslo's Gardermoen airport, the country's largest airport.

Five airports closed Friday over the wage strike including Bergen and Molde, and on Saturday a sixth airport was closed.

Oslo Gardermoen, used daily by 60,000 passengers, would remain open, but 48 flights were due to be cancelled impacting some 5,000 passengers, airport officials said.

The Norwegian civil aviation authority Avinor and unions have not held any meetings since mediation efforts failed early Friday, and a further six airports could be shutdown Tuesday over the labour action.

The airport closures were due to insufficient staff to respond to possible emergencies or fires.

Passengers were advised to consult websites operated by respective airlines over cancellations and if possible look into alternative travel means. (dpa)