GCHQ has revealed this year's official Christmas card from its director Sir Jeremy Fleming - containing a brainteaser aimed at aspiring young spies.

The card contains seven "fiendish" puzzles specifically designed for secondary school pupils aged 11 to 18 to solve, but everyone is being encouraged to take on the challenge.

Sir Jeremy's Christmas card, which includes a festive brainteaser every year, is traditionally sent to national security staff and partners across the world who work alongside the intelligence and security organisation every day to combat organised crime gangs, terror groups and hostile states attempting to do harm to the UK.

But this year, the puzzles have been created for youngsters to tackle over the holidays.

This year's GCHQ Christmas card containing a brainteaser of seven 'fiendish' puzzles

This year's card sets a not-so-secret mission through a set of puzzles that increase in difficulty as you move through the challenge.

In a statement, Sir Jeremy said that "problem-solving skills and teamwork are absolutely crucial" in keeping the country safe.

He added: "That's why this year's Christmas puzzles are aimed at young people. I am keen to encourage STEM skills, thinking differently, and help foster the next generation of talent.

"I want to show young people that thinking differently is a gift, and it is only with a mix of minds that they can solve seemingly impossible problems, just like we do at GCHQ."

Sir Jeremy also recorded a special good luck message for schools.

In recent years, GCHQ has partnered with the organisation Stemettes on several activities to support greater take up of STEM subjects - Science, technology, engineering, and mathematics - particularly among young girls.

Supporting this year's Christmas card challenge, the chief executive of Stemettes, Dr Anne-Marie Imafidon, said: "No matter your age, STEM skills, critical thinking, and problem-solving are important skills to have.

"In my work across the Stemettes with partners like GCHQ, we want all kinds of people to have the chance to explore these skills, and for those that enjoy this type of challenge to get an opportunity to further themselves in these areas."

She added: "GCHQ's Christmas Challenge is a fun festive way to do this, and I'd encourage schools and those who work with children to explore this type of activity as another way to engage the next generation in some light-hearted STEM fun."

Download GCHQ's Christmas card here.