Air and rail services to Delhi were hit on Saturday as a thick blanket of fog enveloped the city and adjoining areas in the early hours of the morning, leaving hundreds of passengers stranded.

Air services at the Indira Gandhi [Images] International Airport were suspended on Staurday morning as Runway Visibility Range dipped to below 50 mt at 7 am forcing suspension of flights.

"All domestic departures remained suspended in the early morning hours," an airport spokesman said.

At least two Delhi-bound international flights, that could not land at the IGIA, were diverted to Mumbai and Karachi.

President A P J Abdul Kalam's departure to Mumbai was also delayed due to the inclement weather.

The RVR had improved to 300 mt at 10.30 am and six Indian Airlines flights took off using the CAT III B Instrument Landing System. Six international flights -- three arrivals and three departures -- also operated from the IGIA.

Several trains coming to Delhi were delayed due to dense fog in the eastern and northern parts of the country.