Tens of thousands of jobs in the aviation sector are at risk unless the government further relaxes rules on international travel, ministers have been warned. New rules allowing fully vaccinated passengers from the United States and amber-list European countries to avoid self-isolation on arrival in the UK came into force at 4 a.m. on Monday morning. But despite the relaxation of quarantine requirements, uncertainty continues around international travel, with Prime Minister Boris Johnson being warned not to create a new category in the traffic light system. The rumoured amber watchlist would apply to countries at risk of being moved into the red category—which requires hotel quarantine for 10 days at a cost of £1,750 for an adult. Reports have suggested there is a fallout among Cabinet ministers over proposals to introduce an amber watchlist, designed to warn travellers of the possibility that countries with concerning coronavirus data—which could potentially include …