A cloud of ash from an erupting volcano in southern Chile has disrupted air travel from South America to Australia and New Zealand, causing widespread delays.

A flight carrying United Nations Secretary-General Ban Ki-moon to Buenos Aires, Argentina was diverted to the northern city of Cordoba late Sunday because of the ash, which can damage aircraft bodies and engines. Mr. Ban was forced to travel to Buenos Aires by bus overnight for a meeting with Argentine President Cristina Fernandez de Kirchner.

The Australian carrier Qantas said all flights in and out of the southern island of Tasmania and to New Zealand remained grounded Monday, but it lifted a ban on flights to and from the southern Australian city of Melbourne. Air New Zealand and Virgin Air decided to resume flights by flying under or around ash clouds.

The volcano in the Puyehue-Cordon Caulle chain in Chile has been erupting for several days, putting South American air travel into chaos as it spews ash high into the atmosphere. In addition to Argentina and Chile, flights have been disrupted in Brazil and Uruguay.