France recommended its citizens leave the Tokyo region today, citing the risk of further earthquakes and uncertainty over damaged nuclear plants.
A statement on the website of the French embassy in Japan noted that Japan's meteorological office saw a 70 per cent chance of a strong fresh aftershock in the north of the Kanto (Tokyo) region in the next three days.
"It seems reasonable to advise those who do not have a particular reason to stay in the Tokyo region to leave the Kanto region for a few days," it said.
"We strongly advise our nationals not to travel to Japan and we strongly recommend delaying any journey planned."
The US State Department issued an updated travel warning today urging American citizens to avoid going to Japan.
The department said it requested all non-essential US government personnel to defer travel and urged American citizens to avoid tourism and non-essential travel to Japan.
It said that strong aftershocks were likely for weeks.
Flights have resumed at all airports closed by the earthquake, except for the airport in the coastal city of Sendai, which remains flooded, the department said.
In Tokyo, most public transportation including trains and subways was operating, the department said.
But many roads have been damaged in the Tokyo area and in northern Japan. In the far-northern Iwate prefecture, toll road highways are restricted to emergency vehicles only, it said.
Britain and Germany advised nationals against non-essential travel to areas affected by Friday's earthquake and a tsunami that is estimated to have killed more than 10,000 people.
The French embassy said the other scenario was that one of Japan's nuclear reactors could explode, releasing a radioactive plume of smoke.
"This plume could reach Tokyo within a few hours, depending on the direction and speed of the wind," its statement said. "The risk is that of contamination."
"The coming three to four days will be critical," it added.
The embassy said its citizens living near the nuclear reactors should remain at home, with air conditioning switched off and wear breathing masks if they have to go outside.
Agencies