Photo taken on Dec. 22, 2020 shows the closed Port of Dover in Dover, Britain. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)

Photo taken on Dec. 22, 2020 shows the closed Port of Dover in Dover, Britain. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)

Photo taken on Dec. 22, 2020 shows the closed Port of Dover in Dover, Britain. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)

Vehicles line up outside the entrance of the closed Port of Dover in Dover, Britain, on Dec. 22, 2020. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)

Photo taken on Dec. 22, 2020 shows the closed Port of Dover in Dover, Britain. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)

Vehicles line up outside the entrance of the closed Port of Dover in Dover, Britain, on Dec. 22, 2020. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)

An electronic sign showing "French Borders Closed" is seen at the closed Port of Dover in Dover, Britain, on Dec. 22, 2020. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)

Photo taken on Dec. 22, 2020 shows the closed Port of Dover in Dover, Britain. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)

Vehicles line up outside the entrance of the closed Port of Dover in Dover, Britain, on Dec. 22, 2020. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)

Trucks are seen parked near the closed Port of Dover in Dover, Britain, on Dec. 22, 2020. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)

Photo taken on Dec. 22, 2020 shows the closed Port of Dover in Dover, Britain. Rapid turnaround lateral flow tests on lorry drivers with the help of the British military are expected as part of the measures to unblock cross-channel trade between Britain and France, British media reported Tuesday. (Photo by Ray Tang/Xinhua)