A new variant of the novel coronavirus is starting to have a big impact on transportation.

After a mutation of COVID-19 started spreading rapidly in southeastern England, some countries have announced a halt to air travel to and from the United Kingdom.

The first to do this was the Netherlands. Belgium followed suit, saying it will stop air connections to the U.K. for 24 hours on Monday (December 21).

Italy also plans to halt air travel with the U.K., whereas the Czech Republic has announced a 10-day quarantine on travellers from the U.K.

The BBC has reported that Ireland is also expected to impose a ban on flights and ferries. Germany and France are also reportedly considering taking measures.

This weekend, British prime minister Boris Johnson announced a new level of restrictions, referred to as tier four, in response to the new variant.

While it's reportedly up to 70 percent more transmissible, there's no proof at this point that it's any more deadly or any more resistant to vaccines than the more common strain of COVID-19.