In just 100 days the Olympic Stadium will be filled with athletes, performers and excited crowds as the official opening ceremony for this year’s Olympic Games takes place – and London won’t disappoint, according to the man in charge of delivering the Games.

Today is exactly 100 days to go until the start of the Games, and is being marked by the planting of an oak tree to celebrate the UK’s role in the birth of the modern Olympic movement.

Also to be revealed today at a ceremony at Kew Gardens, attended by Seb Coe and Paul Deighton, chairman and chief executive of the London Organising Committee of the Olympic and Paralympic Games (LOCOG) respectively, are giant Olympic rings made up of 25,000 flowers.

Lord Coe said: “With 100 days to go to the start of the Games, millions of people are getting ready to do the best work of their lives and welcome the world this summer.

“There is a groundswell of support and excitement, not just in the UK, but internationally as the final countdown to the London 2012 Olympic Games begins.

“Whether it’s the competing athletes or people getting ready to join their communities in supporting Torchbearers on the streets of the UK, the whole world is getting ready for London.

“Expectations are high, and we won’t disappoint.”

Final touches are being made to the Olympic Park and venues across London, including Wembley and Greenwich Park, test events are going ahead and preparations are being made for the Olympic Torch Relay, which starts on May 19.

Still working on the Games are organisations including the Olympic Delivery Authority (ODA), which has been responsible for constructing the new venues for the Games and bringing those already in place up to standard. It has also been working with Transport for London on transport plans.

Dennis Hone, chief executive of the ODA, said: “We’re in the final strait now.

“When the International Olympic Committee came over they said we’d done a fantastic job.

“We’re trying to make sure everyone is doing their best.”