The cabinet minister minister also insisted that people shouldn’t be “too exuberant” as Covid measures are relaxed more generally, with people allowed to meet with others inside in groups of six for the first time this year in England.
As part of the relaxation of restrictions, the biggest step out of country’s third national lockdown, ministers have eased rules governing travel with the traffic light system — rating countries green, amber and red — coming into force.
On Monday morning, British holidaymakers begun checking in for some of the first flights, including to the popular destination of Portugal, which gave the green light for inbound passengers just last week.
Speaking at the weekend, the health secretary, Matt Hancock, however, stressed that people should “certainly not” go on holiday to countries on the amber list, including Spain, Italy and France.
Under the new rules, people arriving back in England from an amber list country must quarantine at home for a period of 10 days and take a Covid-19 test on or before day two and on or after day eight. Those travelling from green list countries are not required to self-isolate, but must still take Covid tests.
Watch: COVID-19 - Is it OK to book a holiday to an amber list country?
Pressed on the health secretary’s comments, Mr Kwarteng told Sky News: “I think what he says makes sense — again, people are allowed to do things, but it doesn’t mean everybody should be going away at the same time. I think the urge for caution makes sense.
“I think what Matt is saying is yes you can go to another country but it would probably be advisable at this stage not to.”
Quizzed on whether it would have been more sensible to ban travel to a country not on the green list, he replied: “There’s a balance between opening things up, urging people to exercise caution and openings things up safely. That’s a good balance I think.”
Mr Kwarteng also insisted he was “very confident” the country would be able to fully re-open on 21 June — the last stage of the government’s roadmap — but also stressed that he could not give a guarantee.
As the country entered Stage 3 of the roadmap on Monday, Boris Johnson urged people to use a “heavy dose of caution” as the increase in cases of the variant first identified in India caused alarm.
Speaking on BBC Radio 4’s Today programme, Sir Jeremy Farrar, a member of the government’s Scientific Advisory Group for Emergencies, echoed the view of his colleague on Sunday that restrictions may have to be reversed if the new variant “escapes” protection afforded to people by the Covid-19 vaccines.
Sir Jeremy, who said he would not meet indoors “at the moment”, despite the rules now allowing him to do so, added: “The new variant that has come, the B.167, is becoming dominant in parts of the UK.
“Yet vaccination across the country has been extraordinarily successful. I think we will see an increase of cases and infections over the coming weeks as some of the restrictions are lifted, but I think the key question is whether we have decoupled increased transmission and number of people who do get infected from the number of people that get ill and need to go into hospital or with long Covid.
“If we’ve decoupled them, then I think the country can cope with a marginal degree of an increase in transmission.
“So that is the key question and to be honest, we don’t know that today and that is why I think a very careful lifting is reasonable, but we may have to reverse that if there is escape from the vaccine.”
Watch: Should I book a holiday in 2021?