By Agence France-Presse Britain could introduce a 14-day mandatory quarantine for international arrivals to stem the spread of coronavirus, an airline association said Saturday, sparking alarm in an industry already hard hit by the global pandemic. People arriving in Britain by air, sea and rail will be required to self-isolate for two weeks, The Times reported (AFP/File / Tolga AKMEN / MANILA BULLETIN) Tim Alderslade, chief executive of Airlines UK, the trade body for UK-registered airlines, confirmed to AFP that the government had approached it with the idea. Prime Minister Boris Johnson could unveil the measure on Sunday evening, media reports said, when he sets out his roadmap for easing a nationwide lockdown imposed in late March to slow the spread of COVID-19. He has already said he will proceed with "maximum caution" to avoid exacerbating the outbreak in Britain, the worst hit country in Europe with 31,587 confirmed coronavirus deaths. No major changes to the stay-at-home rules are expected next week, although garden centres are expected to reopen on Wednesday. The quarantine measures were first reported in The Times newspaper, which said that anyone coming into Britain by plane, train or boat will be required to self-isolate for a fortnight from early June. Visitors from neighbouring Ireland would be exempt, it said, as would lorry drivers bringing in crucial supplies -- but the measure would include British nationals returning from abroad. The rule would be enforced through spot-checks on the address given by travellers, with possible penalties including fines of up to £1,000 ($1,200, 1,100 euros) or deportation, The Times said. The aviation industry, which is already teetering on the brink after planes were grounded across the globe at the start of the virus outbreak, called for urgent clarity on the plans. Airlines UK had previously warned a quarantine would "effectively kill international travel to and from the UK", making it "all but impossible for aviation to resume any time soon". In a statement on Saturday, Alderslade said the group needed to see more details of the plan and would be asking for assurances the decision was "led by the science" and would be regularly reviewed. "We also need to see a number of new support measures to see airlines through this period so that we still have a UK aviation sector once the quarantine period is lifted," he added. Derek Provan, chief executive of AGS Airports, which owns and operates several regional British airports, also expressed alarm. "This measure will have a devastating effect on aviation, tourism and hospitality as inbound visitors will not come to the UK whilst this is in place," he said. The government declined to comment on the plans on Saturday, but Johnson's spokesman on Friday had confirmed the idea was under "active" consideration. At the start of the global outbreak, Britain asked visitors from hotspots such as the Chinese city of Wuhan and northern Italy to self-isolate on arrival. But it refused to follow other countries in shutting its borders, saying coronavirus was already in Britain. If infection rates fall enough to start lifting the lockdown, officials say that putting foreign visitors into quarantine might help stop a new surge. Separately, Transport Secretary Grant Shapps announced plans to increase and improve cycle routes and widen pavements across England in the coming weeks, to boost cycling and walking. He warned that when the lockdown is eased, continued social distancing measures mean the public transport network will only be able to cope with one tenth of pre-outbreak passengers.