The great Eliud Kipchoge is the last of the elite men to be introduced.

He gets applauded by every one of his fellow competitors on this startline.

Denise Lewis gets them under way and the masses follow behind.

Here we go. A special, special day is now truly under way.

Steve Cram
Athletics commentator on BBC Radio 5 Live

It's going to be warm. Plenty of hydration is important.

Take it easy early on. The first few miles are quick. Don't look at your watch and think 'wow I am going much faster than I normally do, that's cool'.

It's not cool. You haven't turned into Paula Radcliffe overnight.

Stick to your normal plan. Don't let the nerves and excitement go a bit quick in the first five or six miles because you will pay for it later.

If you're watching on BBC One (or at the top of this page) you will have seen an emotional interview with Sergio Aguiar and David Stancombe, whose daughters were killed in the Southport attack last year.

They are both running today to raise money for projects set up in their daughters' memory and have received a good luck message from Prime Minister Sir Keir Starmer.

"Even now it still blows me away that so many people know about it and you're getting messages from the prime minister," David said.

In a video message, played to the families ahead of the race, Sir Keir said: "David and Sergio, I want to wish you the very best of luck in the London Marathon this weekend. I know how much it means to you and your families.

"This is an incredible way to honour the memory of your precious daughters and the entire nation is in awe of your courage and your resilience."

BBC One

Seven-time Olympian Jason Kenny, speaking to BBC: "I am very, very excited. I have never been before so this is my first time. It is amazing to see the blend of elite athlete and the buzz of the other 56,000 people running."

McFly drummer Harry Judd: "I am more nervous now than I have been for any gig! This is like my fifth one but I am still nervous. It's such an incredible event, we are here for the bigger reason of raising money for charity but the atmosphere is the best marathon in the world."

Singer Alexandra Burke: "I am really nervous. I am doing it and that is for my late mum. I am here to embrace what today brings and I feel really honoured and privileged to be here today. I'm just taking it all in."

Image source, Getty Images

As ever there are a host of celebs taking part in the marathon this year. Here are just a few to watch out for:

Sir Jason Kenny - Team GB's most successful Olympian

Sir Andrew Strauss and Sir Alastair Cook - former England cricket captains

John Terry - former England and Chelsea football captain

Alexandra Burke - X Factor winner

Joe Wicks - fitness coach and TV personality

Adele Roberts - radio DJ

Imogen James
Live reporter

Three life-changing surgeries as a baby and years of health issues have led Abi Macneil, 24, to running her first marathon today.

Supporting Bowel Research, Macneil tells me the charity is close to her heart as she was born with the rare Hirschprung’s disease.

This is a rare condition which causes a blockage of the bowel and can lead to life-long issues with bowel control.

The work they do is an “amazing step forward” she says, as the charity works on supporting studies treating the disease.

She’s nervous about “hitting the wall” during the run today but cites the support of her friends and family over the “last few months”.

“Without them I wouldn’t have been able to cross the line.”

But she’s excited too. Collecting her bib a week before made it feel “very real”.

We’ll check back in with Abi later – good luck!

Steve Cram
Athletics commentator on BBC Radio 5 Live

Alex has been very realistic. We should all very excited and intrigued but he is an Olympic champion in the triathlon, not the marathon.

He will be down the field. There is a brilliant field ahead of him. Anything in the two hours 10 minutes to two hours eight minutes would be great. Anything quicker would be phenomenal.

Image source, Getty Images

Alex Yee has already ticked off more than most would in a lifetime. Last year he became the Olympic and world triathlon champion.

You may well remember his dramatic victory in Paris last summer when he came roaring back to take gold.

So how do you follow that? Take part in your first London Marathon among a stacked men's elite field, of course.

"It's been something I've asked [his coach] every single year, but it never really made sense," Yee told BBC Sport's Harry Poole.

"This time we were trying to think what would get me to LA [2028 Olympics] in the best place mentally and physically. It was important to freshen things up.

"It's been really exciting to work on my running after five years of trying to make my swim and bike an appropriate level to be competitive in triathlon.

"It's something I've wanted to do and I'm excited to scratch that itch."

Read more from Alex Yee on his marathon debut

Paula Radcliffe
Former women's marathon world record holder on BBC One

There is so much to look forward to in the men and women's race.

Looking at the women setting off always brings back so many memories. It's about burning off those nerves.

Elish McColgan is settling into it. She's behind the front pack who are the pace setters.

She's watched her mum race over the years, and she's raced herself in the mini marathon, but now she gets to go out and see what she can do on this stage.

It's only the early stages, of course, but Sifan Hassan and Tigst Assefa have positioned themselves in the leading group behind two pace makers.

Eilish McColgan is in the group behind.

Image source, Getty Images

Despite the late withdrawls of Ruth Chepngetich and Peres Jepchirchir, the sight of former world record holder Tigst Assefa and Hassan on the start line means those hopes of a women's record are far from over.

The elite women race separately in London, meaning the time to beat is Jepchirchir's 2024 London winning time of 2:16:16 which stands as the women's-only world record. Both Assefa and Hassan have run faster than that.

Assefa smashed the mixed world record in 2023 by running 2:11:53 in Berlin and has suggested similar could be possible this year.

"I did a half marathon in December and that was a test," the Ethiopian said.

"My preparation for this race is good and I feel like I'm in better shape than I was in Berlin."

Hassan's personal best - 2:13:44 set at the 2023 Chicago Marathon - puts her third on the all-time list of fastest female marathoners and she spoke about wanting to break the 2:10 barrier earlier this year, something only Chepngetich has achieved.

Speaking on Friday, she added: "In the marathon, whether you like it or not you will push.

"Running the marathon teaches you to push.

"I will do my best. I am getting nervous. That is good. When I get nervous I do well."

Image source, Getty Images

The talk of the town this week is whether there could be a record in either the men's or women's elite race.

The men's race is stacked, with Kipchoge, defending champion Alexander Munyao, Olympic champion Tamirat Tola and highly-rated marathon debutant Jacob Kiplimo.

Uganda's Kiplimo, 24, became the first person to run a half marathon in under 57 minutes in February, clocking 56:42 to shatter the previous mark by 48 seconds in Barcelona.

That performance has convinced many that he could become the first person to break the two-hour barrier in a competitive marathon, after Kipchoge proved that was possible in controlled conditions in 2019.

The late Kelvin Kiptum's 2023 men's course record is 2:01:25, while his world record stands at 2:00:35.

Eilish McColgan, running her first marathon after so much success on the track, gets a big cheer on the start line.

With a beaming smile as ever, Sifan Hassan waves to the crowd too.

The wheelchair racers are already down the road and now this stacked women's race begins too...

Image source, Getty Images

It has not been a straightforward route for Eilish McColgan to get to this start line.

She was supposed to race in 2023 but injuries prevented her participation.

McColgan is a European and Commonwealth medallist, having previously competed over 3,000m, 5,000m, 10,000m and half-marathon distance, while her mum, Liz, won the London Marathon in 1996.

"I obviously have my mum's PB in the back of my mind," McColgan said. "There's part of me that would love to break that.

"It's the last of her records that I haven't broken. Then there's the Scottish record.

"I've got nothing set in stone. They are loose goals and, if I have a good day, it will happen."

Image source, Getty Images

The build-up to the women's race has been hit by two high-profile withdrawals - world record holder Ruth Chepngetich and 2024 winner Peres Jepchirchir.

A stacked line-up still features two of the three fastest women in history, however.

Olympic champion Sifan Hassan, who dramatically won on her debut in London in 2023, and Paris 2024 silver medallist Tigst Assefa will both race.

Eilish McColgan will make her belated debut, competing over 26.2 miles for the first time after injury prevented her participation in 2023. Her mum, Liz, won this race in 1996.

Among the Britons joining McColgan in the women's race are Charlotte Purdue, Rose Harvey and Phily Bowden.

Baroness Tanni Grey-Thompson
Six-time London Marathon wheelchair champion on BBC One

Image source, Getty Images

Never write off David Weir in terms of how he is performing. He is very smart in terms of picking the right lines.

Marcel Hug did really well in Boston. He broke the pack early. But he gets stressed out by Dave.

When he races well he races brilliantly but he doesn't always back up back-to-back.

The 45th London Marathon is officially under way as the elite wheelchair races begin.

The heat may well help these racers...

Image source, PA Media

An enforced break through illness followed by the arrival of her two children has meant a rollercoaster few years for two-time Paralympic wheelchair racer Jade Hall.

But with a renewed enthusiasm for the sport, she will line up in Sunday's London Marathon just 13 months after giving birth to her daughter via Caesarean section.

"There was definitely a point where I didn't think I was going to be able to race again," the 29-year-old told BBC Sport.

"I was ill for about eight months and in that time everything was hard. My heart rate was elevated when I was just walking around and that was causing chest pains and other symptoms.

"LA [2028 Paralympics] is at the back of my mind but I want to see how the next year goes and how I can earn my place back on the marathon circuit, so I feel like it's one step at a time for me right now."