Flight movement at the Indira Gandhi International airport came to a stand still after the dense fog enveloped the area reducing the runway visibility 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, they said.
The poor RVR forced the authorities to implement Low Visibility Procedures (LVP). Though some flights took off using CAT-3B system.
About 10 flights scheduled to take off were delayed by 2 to 3 hours.