New Delhi/ Srinagar, Feb 6: Most of northern India was enveloped by a dense fog on Wednesday, which disrupted normal life and flight movement.

At Indira Gandhi International Airport, the runway visibility was reduced to around 100 metres on Wednesday morning.

"As of now no flight movement, take off or landing, is taking place due to the heavy fog," airport officials said.

"The Runway Visibility Range (RVR) dropped to 100 metres at around 6.15 am suddenly, " officials said.

The airport authorities were forced to implement Low Visibility Procedures (LVP) due to poor RVR.

Around10 flights were delayed by 2 to 3 hours. Some of the flights took off using CAT-3B system.

The Kashmir Valley too is cut off from rest of the country due to heavy snowfall.

The Srinagar-Jammu National Highway has been closed and the Jawahar tunnel is blocked by six-feet of snow.

Heavy snowfall also hampered movement of road traffic and hit flight schedules in the State.

The tourist spots of Gulmarg and Pahalgam, are also covered by snow, while Srinagar is covered by six inches of snow. (ANI)