Kate Middleton and Prince William visit Birkenhead for first joint engagement this autumn - best photos

The Duke and Duchess of Cambridge have carried out their first joint engagement of the autumn, with a visit to Birkenhead on Thursday. They were joined on the day by Sir David Attenborough for the naming ceremony of the polar research ship the public voted to call Boaty McBoatface. However, that name was vetoed and the ship was officially named the RRS Sir David Attenborough in a ceremony at the Cammell Laird shipyard in Merseyside.

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Prince William and Kate were given a tour of the ship and met a team of engineers, including young apprentices, who have been involved in the build. Accompanied by Sir David, they also met with scientists, who demonstrated the state-of-the-art equipment used to carry out research, and schoolchildren involved in the British Antarctic Survey's (BAS) Polar Explorer programme. Click through the gallery to see all the best pictures from the day's engagement…

Prince William, Kate and Sir David gathered on the deck of the ship to wave to the crowds who had turned out for the naming ceremony.

William and Kate shared a joke as they prepared to name the UK's new polar research ship, the RRS Sir David Attenborough.

The royal couple were joined at the event by the man of the moment.

Kate looked typically elegant in a periwinkle-blue Alexander McQueen coat and carrying an Asprey bag.

The royal couple received a warm welcome as they arrived at the Cammell Laird shipyard in Birkenhead, Merseyside.

Owned by the Natural Environment Research Council (NERC) and operated by the British Antarctic Survey (BAS), the RRS Sir David Attenborough will enable world-leading research to be carried out in Antarctica and the Arctic over the next 25 to 30 years. 

Weighing around 10,400 tonnes - that is 1,400 elephants combined - the research ship hosts a wide range of specialist scientific equipment that will allow researchers to study the ocean, seafloor and atmosphere. It will operate in both Antarctica and the Arctic and will be able to endure up to 60 days in sea ice without being refuelled.

The trio were in high spirits during their visit to Birkenhead. The Duchess had the honour of christening the ship with a bottle of champagne. Kate previously carried out the tradition for the naming of the Royal Princess cruise ship in Southampton, during one of her last engagements before she gave birth to Prince George in 2013.

William and Kate's last engagement together was in August, when they competed against one another in the King’s Cup sailing regatta on the Isle of Wight. Their eldest children Prince George, six, and Princess Charlotte, four, were there to cheer them on.

Sir David, 93, enjoys a close relationship with the royal family, famously appearing alongside the Queen in a documentary titled The Queen's Green Planet in 2018.

Hundreds of people gathered to catch a glimpse of the famous trio.

In his speech, William thanked everyone for "braving the weather" before paying tribute to the ship, which he described as a "true British marvel". He colluded his address by joking: "It is my immense privilege and relief to welcome Sir David Attenborough, rather than Boaty McBoatface, to speak."