The disruption had been predicted late Tuesday, with Transport Minister Philippe Tabarot telling CNews television he was "hoping the situation returns to normal this afternoon".

All public bus services in Paris and the surrounding suburbs were also suspended due to icy roads, though the vast majority of metro and suburban rail systems were working, transport officials said.

The Meteo France weather service said 38 of the country's 96 mainland departments were on alert for heavy snow and black ice, with three to seven centimetres (around one to three inches) of snow already accumulated.

It said the cold snap was of "rare intensity for the season", and authorities had already warned people in the Paris region to avoid unnecessary travel and work at home if possible on Wednesday.

Six people have died in weather-related accidents in France during Europe's bitterest cold snap this winter so far.