In the Argentine capital, flights in and out of the mainly domestic service airport Aeroparque were back to normal while the international airport Ezeiza resumed flights though with some delays. Dozens of flights had been delayed or cancelled throughout the day.

Operations were normal at Ezeiza international airport, south of Buenos Aires, although delays from Tuesday forced some flights to be rescheduled.

At Montevideo's Carrasco International Airport, operations were back on track after two flights were being rescheduled -- one to and the other from Buenos Aires. On Tuesday, 15 flights had been cancelled in and out of the Uruguayan capital's main airport.

Aeronautic meteorology chief Laura Vanoli told AFP that the ash cloud was "still on the southern portion" of Uruguay, while the latest report from the regional office in Buenos Aires could not delimit the area due to heavy cloud cover.

The Puyehue volcano has been causing air travel mayhem since it rumbled back to life on June 4 for the first time in five decades, belching billowing clouds of dust and ash.

Flights across South America -- including from hubs in Montevideo, Chile's capital city Santiago and southern Brazil -- have all been hit as ash clouds swept around the southern hemisphere to linger over Australia and New Zealand.

The Puyehue volcano is high in the Andes Mountains, 870 kilometres south of Santiago near the border with Argentina.

Copyright AFP (Agence France-Presse), 2011