Private airlines IndiGo and Vistara on Monday issued travel advisory for their passengers saying flights to and from the national capital have been impacted due to bad weather and poor visibility.

Dense fog and eventual poor visibility have caused flight delays and cancellations across north India in the past few days.

In a tweet on Monday, IndiGo said: "#6ETravelAdvisory: Due to poor visibility in #Delhi, our flights are impacted. Do keep a track of your flight status."

Vistara also said that its flights to and from the national capital have been delayed affecting its other flights too.

"Due to dense fog and poor visibility in Delhi, arrivals/departures from Delhi are delayed with consequential impact across the network," it said.

Early on Monday, Budget airline SpiceJet also asked its passengers, scheduled to travel to and from Delhi to keep a track of their flight status.

"Due to bad weather at Delhi (DEL), all departures/arrivals and their consequential flights might get affected. Passengers are requested to keep a check on their flight status," the airline tweeted.