Holidaymakers risk being hit with a £1,000 on-the-spot fine for leaving home within two weeks of returning from a foreign trips.
Those who repeatedly flout the rule could be prosecuted. It means households face a choice between not jetting abroad for a break, or enduring 14 days of effective house arrest.
Those hoping to travel to hotspots such as the Balearic Island of Mallorca or the Costa del Sol in Spain later in the summer could find themselves grounded.
The 14-day quarantine comes into force on June 8. It will be reviewed after three weeks. Tourism chiefs and business leaders slammed the decision, which comes four months after the first Covid-19 case in the UK was confirmed.