British Airways Chief Executive Officer Willie Walsh and other airline executives react ed in anger to the new round of flight restrictions, The Daily Telegraph reported Tuesday.
Airlines have lost about $1.5 billion since a plume of gray ash began to cover parts of Europe in mid-April. Walsh said the flight restrictions were "a gross overreaction to a very minor risk."
The Civil Aviation Authority announced it had loosened its restrictions and would allow flights through a greater density of ash than in the past.
The ash restricts visibility, but the solid particles can also clog jet engines. An Icelandic geophysicist, Magnus Tumi Gudmundsson, said the volcano has spewed 8.8 billion cubic feet of ash into the atmosphere.
In a related story, a British court approved of an injunction stopping BA flight crews from proceeding with a series of planned strikes, although BA said the injunction came too late to reinstate many flights that had been canceled in anticipation of a five-day walkout.