SUVA, March 23 (Xinhua) -- Fiji Airports have advised all air traffic controllers to return to work as the authorities are looking into their grievances.

The advice came on Saturday as about 33 Fijian Air Traffic Management (ATM) controllers have taken various forms of leave since March 18 while demanding increases in their pay from the Airports Fiji Limited Management.

Fiji Airports said a pay rise is under contemplation with two internal papers already under discussion.

However, the company said it is opposed to the manner in which a pay rise was being demanded under a threat by the air traffic controllers who have been on strike this week.

It also said that in the last five years, from 2013 to 2018, air traffic controllers on average earned 61 percent more in gross pay, for 43 percent less workload in overtime. The reduction in workload is attributed to increase in numbers by 31 percent in that period.

Fiji Airports said this gross pay is made up of the three pay rises and multiple allowance increases in 2014, 2015 and 2017, plus promotions within the ATM structure through active training that they conduct with their controllers.

The company also said that contrary to irresponsible statements by the striking workers'representative Kolokesa Kini, no air traffic controller has been working continuously for 96 hours.

Fiji Airports said it has put in place an approved procedure that significantly reduces the workload and traffic congestion in Fiji's airspace.

There are 130 circuit training flights in a day in the Nadi airspace which have been restricted in deference to safety. The company said on average 30 international flight movements and 50 domestic flight movements in a day, which are their main priority.

Fiji's Employment Ministry has declared the conduct of air traffic controllers at Nadi International Airport as an unlawful strike on Friday and urged them to return to work.

Air traffic controllers are adamant they will not return to work until Fiji Airports agrees to negotiate on their pay.