"The volatility of sterling-dollar combined with the volatility of the oil price definitely makes it much more challenging for airlines based in the UK who have a strong sterling revenue base but a strong dollar cost base; not just Virgin," Willie Walsh, director general of the International Air Transport Association, said on Tuesday.

"So I have a lot of sympathy for him," he told reporters when asked about alarm voiced by Virgin Atlantic CEO Shai Weiss.

(Reporting By Allison Lampert in Montreal and Tim Hepher in Paris)