Several ground service staff at Geneva airport announced a strike on Sunday, which their union said was expected to slow travel over the holiday period over a dispute with their employer, the Dubai National Aviation Association (Dnata).

Dnata workers, who handle about a quarter of the traffic through Geneva's Cointrin International Airport, began the strike at 4am (3 GMT) on Sunday.

The strike will slow travel as it peaks over the Christmas period, when around 60,000 people are expected to travel through the airport on Sunday.

dnata employees handle various ground services such as ticketing and baggage handling for several international airlines including British Airways, Air France and KLM.

The union, which has been threatening the move since the start of the week, said the strike was estimated to last “hours”, according to online news site “20Minute”.

Workers at Emirati airport services company Dnata are demanding a five per cent increase in their salaries.

They are also demanding that the company pay extra for some jobs that require manual labor, which Dnata has refused, union representative Jamshed Pooranbir said on the website.

Dnata offered to raise salaries by three percent and agreed to drop a controversial plan to cut contributions to the employee pension fund, but that was not enough to satisfy workers.

Dnata representative Alexander Koenig told the site that the company is “committed to reaching an agreement” and would consider any strike action “illegal.”

The news site reported that the union condemned the “pressure” exerted by the company at the same time, saying it threatened to fire striking employees.