International Air Transport Association chief executive, Giovanni Bisignani, has launched a surprise attack on British Airways’ staff, as a walkout by trade union members enters its fifth day. Bisignani described the current labour dispute as unbelievable at a time when the entire airline industry is struggling to pull itself out of a crippling recession.

The trade body leader said that deciding to strike in the current economic climate showed that Unite members were divorced from reality. He added that airline employees must realise that their paycheques were reliant on the performance of the company that they worked for, and that at the moment, the economic turbulence in the world made business extremely tough.

The condemnation of the behaviour of BA staff come as IATA announced its official figures for the disruption caused by the volcanic ash cloud which settled over Europe last month. Airline traffic in Europe during April fell by 11.7 per cent, according to the transport association. Around the world, passenger traffic dropped by 2.4 per cent. This is the first drop in passenger levels since last August, and much of the blame is being put on the Eyjafjallajökull volcano eruption.

Over a period of six days last month, air traffic authorities grounded 100,000 aircraft across Europe. The move caused enormous frustration for both passengers and airlines. Airline bosses have been furious at what they see as unnecessary disruption at a time when most are struggling to cope with the aftermath of a global recession.

Bisignani said that the effects of the ash cloud over Europe had pushed back global economic recovery.