The British government “panicked” when it decided to impose a 14-day quarantine on visitors returning from Spain, according to the Ryanair chief executive, Michael O’Leary, who called the move a “badly managed overreaction”. The requirement for all visitors arriving in the UK from the country to self-isolate for two weeks came into effect on Sunday, only hours after it was announced. The chief executive of the Irish airline said there had been very little upward movement in cases of Covid-19 around Spain’s resort towns or in the Balearic or Canary Islands. “They should have, in my view, controlled arrivals back in from Catalonia, or done it on a regional basis, but to do it on a national basis, there is no scientific basis for a national restriction on visitors coming back from Spain to the UK,” O’Leary said. “We wouldn’t expect other EU countries to impose quarantine on all UK visitors just because there has been a spike upwards in Leicester,” he added, referring to the local lockdown that was imposed in and around the east Midlands city. The global airline body the International Air Transport Association (Iata) also criticised Britain’s decision to impose new quarantine requirements, and described it as a “big setback for consumer confidence that is essential to drive a recovery”. Iata said in a statement that a blanket quarantine order affecting all travellers from Spain to the UK “does not accurately reflect the risk of a regional spike in one corner of the country”. The UK government has advised against all non-essential travel to the Spanish mainland due to recent coronavirus outbreaks. Despite this, Ryanair will not reduce the number of flights to and from the country. Airline and travel stocks tumbled across Europe on Monday morning amid fears of further travel restrictions. The British Airways owner, IAG, was the biggest faller on the FTSE 100 index in London, down 9.5%, while easyJet lost 13% and Ryanair fell 8%. Europe’s biggest holiday company, Tui, lost 15% on the German stock market after its UK arm said it would cancel all holidays to mainland Spain up to 9 August, but maintain flights to the Balearic and Canary Islands. The German flagship carrier, Lufthansa, fell more than 7%. Other airlines including British Airways and easyJet have strongly criticised the UK government’s decision but have said they will continue to operate flights despite the quarantine rules. Ryanair is operating at 40% of its capacity across 90% of its network and aims to increase to 60% of capacity during August and potentially 70% during September. It reported a loss of €185m (£169m) during the first quarter of its financial year, during which almost its entire fleet was grounded because of the pandemic. It resumed flying on 1 July across most of its network. The airline said a second wave of Covid-19 cases across Europe in the autumn was its “biggest fear”, and it expected next year to be “very challenging”. O’Leary told airline analysts that he could not rule out further pay cuts or job losses if there was a second wave of coronavirus later this year. The airline hopes the introduction of effective track-and-trace systems by EU governments, the compliance of citizens in wearing face coverings and other hygiene measures such as handwashing will reduce the likelihood of further lockdowns or restrictions on flights across the continent.