To mark the final day of the first wave of four-day strikes by CLH fuel distribution workers, pickets managed to prevent any fuel tankers leaving the main Palma depot yesterday. The first wave of the strike, which started on January 2 and ended last night, had little effect on the driving public in the Balearics, but did manage to disrupt flights and cause a number of delays, some of which were longer than one hour. Last night airlines bated the unions claiming that the effects had been minimal, but union leaders warned that protest action will be stepped up ahead of the second wave of industrial action with the aim of leaving petrol station forecourts dry. Some petrol stations in the heart of Majorca did feel the pinch as in the dying hours of the strike it was feared that fuel deposits would run dry. Union bosses in Palma hailed yesterday as the most successful day of the strike, while the President of the Balearic Association of Petrol Stations, Jesus Salas, said it was the worst day of the strike, thank God it finished last night allowing us to fill up our deposits. Salas said that over the past four days, the strike caused little or no disruption at fuel stations and the expected rush of drivers stockpiling fuel for fears of petrol shortages did not transpire. But we're all concerned about what plan of action the unions are drawing up for the second wave, Salas said. Union bosses warned yesterday that pickets will aim to blockade all fuel depots on January 16 for four days and, if successful, could bring the Balearics to a standstill as petrol stations run out of fuel. UGT General Workers' Union spokesperson, Pedro Bennesar, said yesterday that unless the management changes its attitude the consequences of the next wave could be extremely serious. Airport fuel distribution will also be hit on January 8, 10 and 12.