Mass protests in France spilled over to disrupt cross-Channel transport in Britain on Tuesday.
Dozens of flights and trains were cancelled and ferries delayed as French workers rallied against government pension reforms.
Air traffic controllers and rail staff in France were among those to walk out.
Budget carrier EasyJet axed at least 18 flights between Britain and France while British Airways cancelled at least 13, impacting passengers departing from hubs including Heathrow and Gatwick airports near London.
Air France withdrew four flights from service between Heathrow and Paris.
Eurostar, which runs the cross-Channel rail service, cancelled 16 of 26 trains scheduled between London and Paris, and a further six between the British capital and Brussels.
The company warned the fallout from the protests "could extend beyond" Tuesday.
Ferry passengers travelling between Dover and Calais were told to expect disruption, with sailings delayed by up to 65 minutes. P&O Ferries advised passengers to travel on another date.