Airline passengers in Australia, New Zealand and Argentina had another frustrating day Tuesday as an ash cloud from a Chilean volcano continued to spread in the world's southern hemisphere, according to dpa. The Caulle volcanic cordon in the southern Chilean Andes erupted on June 4, sending ash and other debris into the atmosphere. It has since disrupted the plans of UN Secretary General Ban Ki-moon, Uruguayan President Jose Mujica, the Argentine national football team and thousands of anonymous travellers. Experts have stressed that the eruption could go on for weeks, or even months. Many airlines regard the presence of ash in the atmosphere as a risk to plane turbines, and opt not to fly in such conditions. The situation has already cost airlines millions of dollars. Flights remained cancelled Tuesday in Buenos Aires' two commercial airports, as well as in many others around Argentina. The Argentine capital, an important regional hub, had no flights throughout Monday, as on several other days since the Caulle's eruption started. Argentine authorities decreed a state of emergency in agriculture in portions of Patagonia, where the ash has covered pastures and left 2 million sheep without grazing grounds in the southern hemisphere autumn. The government intends to help sheep farmers, who have already suffered several years of drought. In Australia, Qantas and Jetstar cancelled flights in and out of Adelaide as the cloud spread. Flights to Tasmania remained grounded for the third day. Some flights to Perth were also postponed. Tens of thousands of passengers have been affected as they try to get back to work after a three-day holiday weekend. Virgin Australia continued to operate services to all cities, flying under or around the volcanic ash cloud. Qantas and Jetstar also cancelled all flights in and out of New Zealand, stranding thousands of passengers. Pacific Blue, Virgin and Emirates also delayed or cancelled flights in and out of New Zealand, affecting nearly 20,000 passengers. Air New Zealand was the only airline continuing to fly, keeping its planes below the ash cloud height of 8,229 metres.