The Srinagar-Jammu National Highway was closed on Friday due to snowfall near the Jawahar Tunnel in Qazigund area.
Traffic control authorities said efforts were on to clear the road but continuing snowfall was impeding road clearance operation.
Higher reaches of Kashmir have been receiving intermittent snowfall and rains since Wednesday.
The 294-km highway is the only road link between the Kashmir Valley and the rest of the country.
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