Heathrow Airport will be closed all day Friday after a fire at a nearby electrical substation

Heathrow, the UK's busiest airport, warns of "significant disruption" over the coming days and tells passengers not to travel "under any circumstances" until it reopens.

Heathrow Airport will be closed all day Friday after a fire at a nearby electrical substation that supplies it with power.

At least 1,351 flights to and from the airport in west London could be cancelled today, according to flight tracking website Flightradar24.

The fire at the substation in Hayes, west London, has left thousands of homes without power and 150 people have been evacuated from surrounding properties.

The fire at the substation in Hayes has left more than 16,300 homes without power and caused around 150 people to be evacuated from surrounding properties

The cause of the fire is not yet known