Lady in red: Kate Middleton is elegant in scarlet peplum suit at school visit with Prince William

Having taken part in marathon training with Princes William and Harry on Sunday (5 February), less than 24 hours later, Kate Middleton oozed ladylike elegance on a royal engagement to a London primary school.

The 35-year-old Duchess of Cambridge swapped trainers for stilettos as she joined her husband William at the Mitchell Brook Primary School in Neasden, north London, in her role as patron of the children's charity Place2Be.

Proving that their competitive streaks don't affect their strong bond, the royal couple were in high spirits just one day after they were both beaten by Prince Harry in a fun sprint at London's Queen Elizabeth Olympic Park.

On the official engagement, Kate caught the eye in a red skirt suit by Italian designer Luisa Spagnoli, which proved a stark contrast from her red puffa jacket, jeans and trainers for Sunday's outing.

The chic statement two-piece exuded a Jackie Kennedy vibe with bold tailoring yet subtle feminine detailing including round black buttons and a waist-cinching belt.

The peplum-style suit has been worn by the duchess on several occasions, wearing it on her and William's return to St Andrews University and the couple's 2014 tour of New Zealand. Kate accessorised the striking outfit with a Mulberry black clutch bag and suede court shoes while wearing her hair in a voluminous blow-dried style.

Sticking to the smart memo, William looked dapper in a navy suit paired with a burgundy tie as he stood close to his glamorous wife.

On their visit, the royal couple will meet and greet staff and pupils before attending the Assembly and present the first Place2Be Kindness Cup to a specific pupil who has shown exceptional compassion in the school community. It is part of the Heads Together campaign which was formed by the duke and duchess along with Prince Harry to combat the stigma surrounding mental health.

The subject of mental health was important to William and Harry's mother – the late Princess of Wales – and the princes have done their best to fulfil her legacy. The outing comes as Children's Mental Health Week 2017 (6th – 12th February) is set to focus on kindness and its benefits for wellbeing.

A Place2Be spokesperson said: "It can be difficult to know how to help someone going through a difficult time, but small acts of kindness can make all the difference.

"Throughout the week, Place2Be is encouraging children to 'spread a little kindness' in their schools and at home, for example by looking out for classmates who may be having a difficult time, listening to how they feel, and if they need it, asking an adult for help."