As two more African countries are added to the UK’s flight ban list, ministers are contemplating introducing tough travel restrictions – of the kind that have been in force since last March in Asia and Australasia.

These are the key questions and answers.

Twenty-nine. But the so-called travel ban, aimed at limiting the spread of new variants of coronavirus, does not ban travel from the countries on the list.

Direct flights are not allowed. For the vast majority of locations, this is irrelevant since there were no scheduled services operating anyway.

Some additional restrictions apply to passengers on connecting flights to the UK: British and Irish citizens, as well as third-country nationals with residential rights in the UK, can come in whenever they like but must self-isolate along with their households for 10 days.

Other travellers cannot arrive in the UK if they have been in any of the “banned” countries within the past 10 days.

Tanzania and Democratic Congo are now on the list, joining nine other mainland African nations: South Africa, Namibia, Zimbabwe, Botswana, Eswatini, Zambia, Malawi, Lesotho, Mozambique and Angola.

The transport secretary, Grant Shapps, tweeted: “To help to stop the spread of the Covid-19 variant identified in South Africa, we are banning all arrivals from Tanzania and Democratic Republic of Congo from 4am.”

The addition of these two nations will make no significant difference; the last scheduled flights from either country, a British Airways link from Dar es Salaam to London, ended eight years ago.

Flights from three island nations off the coast of Africa – Cape Verde, Mauritius and the Seychelles – have been banned. In normal times they are popular holiday destinations with direct flights from the UK.

The most significant nation, though, in terms of British visitors and expatriates, is Portugal. At present it is the only European country subject to a flight ban.

“We are continuing to monitor Covid-19 rates and new strains of the virus across the globe, this alongside the suspension of travel corridors and pre-departure testing will help protect our borders,” said Mr Shapps.

Quarantine is also mandatory for all overseas arrivals except for those from Ireland.

But ministers are considering much tougher and wide-ranging rules for arriving passengers in a bid to limit the spread of new variants of coronavirus – including arrivals self-isolating in designated hotels, rather than at home.

Early in 2020, the UK imposed quarantine measures aimed at preventing the spread of the virus from known hotspots including China, Iran and northern Italy. On 13 March 2020 these measures ended. The government said there was no point in continuing to insist on self-isolation because coronavirus was widespread in the UK.

Two days later, Australia’s prime minister, Scott Morrison, imposed two weeks of self-isolation on arrivals from all countries. By the end of March, the law had been strengthened to make “hotel quarantine” mandatory.

Three months later, on 8 June 2020, the UK government made a U-turn, going from no quarantine to quarantine from everywhere, with 14 days of self-isolation required.

A month after that, the concept of “travel corridors” took effect, allowing journeys from most European countries without self-isolation. But by late July Spain had lost exemption, and in the months since then most popular destinations have also had quarantine-free status removed.

In December, the time required for quarantine was reduced from 14 to 10 days, and in England “test to release” was brought in – allowing self-isolation to be halved for those who received a negative test result on day five.

On 18 January 2021, all quarantine exemptions were removed.

At present anyone arriving in the UK is free to take public transport home and stay there for 10 days (which can be reduced in England with a test taken after five days). If necessary, they can stay somewhere overnight on the way to their quarantine location.

Hotels are provided for arrivals from abroad who do not have a household with whom they can self-isolate, but there is no significant supervision.

Of the 12 million arrivals to England since June 2020, 3 per cent (about 400,000) have been checked upon by public health staff to ensure they are quarantining, Mr Shapps has said. The transport secretary added that checks are being increased.

Australia, New Zealand and many Asian nations have imposed hotel quarantine since March 2020. The standard arrangement is for the traveller to be escorted from the airport terminal to a nearby hotel.

They have a number of conditions imposed, usually stipulating that they are not allowed to leave their room – though in some cases limited exercise opportunities are available at specific times.

Meals are delivered to the hotel room. In some cases, alcohol is available, but in many settings it is not.

Security guards are often deployed to try to ensure that quarantinees comply with the rules, and in some destinations hefty fines are levied for those caught breaking them.

Cambodia has a particularly intriguing variation on the theme, with mandatory testing on touchdown. All arrivals must pay US$30 (£22) for an overnight stay at hotel or waiting centre and the same again for three meals a day while waiting for test result.

“If one passenger tests positive for Covid-19, all those on the same flight will be quarantined for 14 days,” says the Foreign Office. 

The cost is US$1,176 (£863) to pay for the stay in a hotel or quarantine facility – but this includes meals, laundry, sanitary services, doctors and security services.

Currently hotel quarantine certainly could. The swathe of restrictions, from a ban on leisure travel for all UK residents to the blanket quarantine requirement, means that almost nobody is travelling at present.

Total daily arrivals to the UK are down from tens of thousands at the start of the year to a few thousand. Heathrow, the main access point to the UK, is surrounded by hotels, almost all of which are near-empty or closed due to lack of custom.

Other airports also have plenty of hotel capacity, with occupancy typically down to single-figure percentages.

Dover and Folkestone have plenty of hotels near the port and Eurotunnel terminal respectively. London St Pancras, the arrival point for Eurostar, has a hotel at the station and many more very close.

The traveller. A rough estimate of the cost is around £1,000 for 10 days in self isolation. For couples together it might be slightly less, for single travellers slightly more.

The test-to-release scheme, which reduces quarantine in England, is likely to be suspended just weeks after it was introduced.

Yes. Ministers are also considering tracking the phones of arriving travellers, to ensure they are complying with the rules, or establishing a system of daily registration with a central data base.

Closing Heathrow, Manchester and other UK airports to passenger traffic could be mandated by the government. But It would cause immense problems for the very few people who are travelling at the moment, and ultimately is unlikely to do any good.

The transport secretary, Grant Shapps, revealed earlier this month that only one in 1,000 of the coronavirus cases in England in December was brought in from abroad – and that was a month with plenty of people travelling, including 1.1 million through Heathrow.

Today the figure is likely to be far lower.