• Video report by ITV News Royal Editor Chris Ship, in Pakistan

The RAF plane carrying Prince William and Kate was forced to make an unscheduled landing last night after being hit by a severe storm over Islamabad.

It threw the plans for the final day of their Royal Tour into chaos.

The jet was attempting to return the couple and their staff to the capital Islamabad after a day of engagements in the city of Lahore.

The jet flew into the storm and twice had to abort landing at the military base in Islamabad.

The Duchess of Cambridge described the journey as "a quite an adventure".

Kate added: "It was pretty bumpy up there, but we were looked after so wonderfully by the RAF, you know, they did a great job liaising with everyone and got us home safely so we are hugely grateful to everyone."

On board, the unexpected turbulence shook the plane and forced the aircrew and passengers to abandon their duties and strap themselves to their seats.

The plane shook violently as lightning flashed around the aircraft.

There were many experienced pilots and aircrew (including Prince William himself) on board last night’s plane.

Every one of them said they had never experienced turbulence anything like that which hit them yesterday.

Storms were predicted in the Islamabad area - but the RAF crew did not expected anything as severe as the weather they then encountered.

Some on board even suggested that, at time, the plane was being blown sideways.

Despite attempting to increase altitude and fly above the storm, the pilots were unable to escape it.

After two unsuccessful attempts to land in Islamabad - the aircraft turned around and flew back to Lahore - landing three hours after it had departed.

Prince William smiled and said that he “was fine” when he came back to check on his staff and the media entourage.

He even joked that he was flying the jet at the time (he wasn’t).

The couple have been in Pakistan as part of a royal tour. Credit: PA

The Duke and Duchess of Cambridge have spent the last 5 days on an official tour of Pakistan.

The RAF jet is being used by William and Kate, their household and the members of the media covering this 5-day tour.

The final day is having to be hasty re-arranged and Kensington Palace was forced to cancel some of the planned engagements for Friday.

The Duke and Duchess of Cambridge have spent the last 5 days on an official tour of Pakistan. Credit: PA

Around a hundred passengers from Kensington Palace, the British High Commission, security personnel, the RAF and the press boarded the plane in Lahore yesterday evening.

The jet is an RAF Voyager which is the designated VIP plane on which the Prime Minister, and senior members of the Kensington travel on official business.

The planes ‘day job’ when it’s not being used on government or royal duties is an air-to-air refuelling plane.

In fact, this jet will return to military duties immediately after it returns from Pakistan.

William and Kate are scheduled to return to the UK later today.