Youhuu is a racka sheep, a type of breed known for its unusual spiral horns.

It is native to Hungary having arrived in the country more than 1,100 years ago, and the distinctive racka breed is not found anywhere else.

The sheep are said to have remained as "faithful companions" to local people ever since their arrival.

Many racka sheep used to be found on the site of the National Athletics Centre - the newly-built flagship stadium which lies by the River Danube and will be used for the World Championships.

Youhuu is described as "an everyday hero who is inspired by the World Athletics Championships to take up sport and loves athletics".

"As the chief cheerleader, he will be an essential part of the event before and during the World Championships, sometimes sweet, sometimes cheeky, but always fun," organisers said.

The mascot was unveiled at a press event in Budapest, where the Championships are due to open 100 days from now on August 19.

They will run through until August 27.

Jon Ridgeon, the chief executive of World Athletics, rang a bell as Youhuu was unveiled at the National Athletics Centre.

He also presented organisers with the official certification for the stadium, a formal declaration that it is ready to host the World Championships.

"We have just completed what we call our 'readiness site visit,'" he said. 

"This is a big milestone as it means we are now running down the home straight. 

"We are delighted with the progress. 

"The Organising Committee is a skilled and experienced team and they have created strong partnerships with key delivery stakeholders across Budapest and Hungary including transport, security, tourism, hotels and many, many more.

"There are still thousands of little decisions and connections to be made but I am confident that the team and their partners and stakeholders will deliver an exceptional event in 100 days time here in this beautiful city of Budapest. 

"Whilst the competition starts in 100 days, around 2,000 athletes from 200 countries, 1,500 broadcasters and 2,500 volunteers will be arriving in Budapest up to one month before the Opening Ceremony. 

"We know they will all receive a warm Hungarian welcome from our hosts."

Balázs Németh, the chief executive of Budapest 2023, also marked the 100 days to go milestone.

"One hundred days before the start of the World Championships, the Local Organising Committee has reached the home straight, meaning that all the plans are in place to show that Hungary is capable of hosting the world's third biggest sporting event to an outstanding standard," he said. 

"More than 10,000 people will be working between 19 and 27 August to impress the more than 2,000 competitors from more than 200 countries participating in the World Championships, as well as the hundreds of thousands of spectators and the one billion TV viewers around the world."

The World Championships will be the biggest sporting event in Hungary's history and 160,000 tickets have already been sold.

"In the last seven years, Hungary and Budapest have established themselves as a global sports capital that has proven its high capability of organising the world's biggest sporting events starting from the 2017 and 2022 World Aquatics Championships through the World Judo Championships and World Fencing Championships or the UEFA Euro 2020 Championship just to name a few," said Balázs Fürjes, co-chair of the 2023 World Athletics Championships governing body. 

"However, the World Athletics Championships will be the biggest event in Hungary's history. 

"Budapest is in the heart of Europe, very accessible from everywhere. 

"It's a mid-size global city, very compact, everything is within arm's reach. 

"The culture is vibrant and we are a sport-loving nation. 

"Budapest is good value for the money and a very safe and secure destination. 

"Budapest is meant to be the host city of major international events. 

"We are honoured that World Athletics chose Hungary and Central Europe for the first time in history. 

"Our country will perform and honour this trust again."