London's two major international airports — Heathrow and Gatwick — reopened to some flights Monday after a no-fly zone was imposed due to dense volcanic ash drifting down from Iceland. Airports in Amsterdam, Scotland and Ireland were still closed.
Yet in a hopeful note, charts published by Europe's air traffic control agency said the ash cloud should be gradually breaking up and retreating during the day.
Eurocontrol said 28,000 flights were expected Monday in Europe, about 1,000 less than normal, mainly due to disruptions in the airspace over Britain and the Netherlands.
Heathrow and Gatwick were operating with noticeable restrictions. Gatwick said it could not accept any arrivals until early afternoon, but about 100 flights were expected to depart. Authorities at Heathrow warned passengers to expect delays and cancellations, and said they would reduce arrivals from 44 an hour to about 30.
Airports in Northern Ireland, much of Scotland — including Edinburgh and Aberdeen — and parts of Wales were still under a no-fly order as winds pushed the ash plume into Europe's busy airspace.
Amsterdam's Schiphol Airport, another of Europe's biggest air travel hubs, was to remain closed until 2 p.m. (1200 GMT; 8 a.m. EDT).
In Ireland, Dublin's international airport closed Sunday evening until at least noon Monday (1100 GMT, 7 a.m. EDT). Some airports in Ireland's west were closed.
Naviair, which manages Denmark's airspace, said airspace over the North Sea was closed until midnight GMT, forcing airplanes to fly around it, and Faeroe Islands airports were closed.
Airports across Britain and Ireland were closed for much of Sunday. Britain's weather service says the northwest winds should shift midweek, redirecting the ash away from Britain.
Germany sent up two test flights Sunday to measure the ash cloud. There was no word yet on the results of those tests.
Ash can clog jet engines. The April 14 eruption at Iceland's Eyjafjallajokul volcano forced most countries in northern Europe to shut their airspace between April 15-20, grounding more than 100,000 flights and an estimated 10 million travelers worldwide. The shutdown cost airlines more than $2 billion.
In southern Iceland, there were "no major changes" in activity at the volcano, the Icelandic weather service said late Sunday. It said the ash plume was higher than in previous days because of calm weather.
It said "presently there are no indications that the eruption is about to end."
Airlines complained bitterly over the air space closures last month, calling them an overreaction. The European air safety agency last week proposed drastically narrowing the continent's no-fly zone because of volcanic ash to one similar to that used in the U.S. The proposal still must be approved.
Eurostar, which runs trains between Britain and continental Europe, added four extra trains — an additional 3,500 seats — between London and Paris on Monday.
Eyjafjallajokul (pronounced ay-yah-FYAH-lah-yer-kuhl) erupted in April for the first time in nearly two centuries. During its last eruption, starting in 1821, its emissions rumbled on for two years.
Associated Press writers Slobodan Lekic in Brussels, Jan Olsen in Copenhagen and Mike Corder in The Hague, Netherlands, contributed to this report.
© Copyright 2016 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.