Controllers at seven Hial airports begin industrial action
Air traffic controllers working for Highlands and Islands Airports Limited (Hial) have started a work to rule in a dispute over their pay.
The Prospect union members plan to work to rosters and not do any overtime until 31 August. A strike is planned for 26 April.
Hial and the union have warned that the action could cause disruption to some flights.
Seven of Hial's 11 airports are affected.
They are Benbecula, Dundee, Inverness, Kirkwall, Stornoway, Sumburgh and Wick John O'Groats.
A meeting is due to take place on 9 April in an attempt to resolve the dispute, involving Hial, Prospect and the Advisory, Conciliation and Arbitration Service (Acas).
The controllers rejected a 2% pay offer made last year. Prospect said the workers' salaries had fallen behind those in the private sector.
Hial said that as a government sponsored agency, it must follow the Scottish government pay policy and cannot implement pay awards more than that directed by government.
The Scottish government has asked Hial and Prospect to continue dialogue in an effort to reach an agreement.