Matt Richards and Tom Dean won 200m freestyle gold and silver to land Great Britain’s first swimming medals of the World Aquatics Championships in Japan.

South Korea’s Hwang Sun-woo took the bronze as 2022 world champion David Popovici of Romania finished fourth.

“I am pretty tired but over the moon. It was a stacked field,” said Richards.

“It’s amazing to come away with the GB 1-2 again.”

The result follows the British gold and silver won at the Tokyo Olympics when Dean and Duncan Scott finished first and second.

“People thought Popovici was going to walk away with the gold so my coach and I had to plan our race and swim sensibly,” Richards told BBC Radio 5 Live.

“But some of those guys have very long arms so I knew I needed to get the finish right.

“It all comes down to not being afraid and trusting in your ability and the work you put in.”

Dean, who won bronze last year, said he was “really excited” to team up with Richards, Scott and 2015 world champion James Guy in the 4x200m freestyle relay on Friday.

“It’s a bitter-sweet result for myself, but I’ve known Matt for years and if there’s anyone to get beaten by, it would be another Brit,” said Dean, 23.

“It bodes well for the relay and really bodes well for the Paris Olympics next year. I am buzzing right now.

“The 4×200 is our specialty, we are Olympic champions and we want to continue the GB reign. No other country can put the team together that we can. I have a lot more races but I am secretly really excited about that one.”

Meanwhile, Britain’s Medi Harris came seventh in the women’s 100m backstroke final – equalling her result from Budapest 12 months ago.

And Freya Anderson swam a personal best 1:55.85 to qualify sixth fastest for Wednesday’s 200m freestyle final, but team-mate Abbie Wood did not progress from the heats.

‘GB 1-2 will give team belief’

Popovici, 18, led from the start in Tuesday’s final and looked set to retain his title but faded badly on the home straight as the two Englishmen closed in.

Former world champion Karen Pickering, commentating on BBC Radio 5 Sports Extra, said: “That was spectacular. Those two boys swam the race perfectly.

“They sat on the shoulders of the other swimmers, dug deep and their closing 20 metres were utter perfection.”

Fellow BBC swimming expert Steve Parry added: “Popovici, the Romanian superstar, dubbed the future of the sport, the reigning world champion, and the British boys have taken him down.

“What a swim from Richards to become world champion.

“GB needed that, but whoever dreamed of first and second? That will give the team belief.”

Britain had narrowly missed out on a medal over the first two days in Fukuoka, with the women’s 4x100m freestyle relay team coming fourth on Sunday and Jacob Peters and Ben Proud finishing fourth and fifth respectively in the men’s 50m butterfly final on Monday.

Richards was part of the British men’s 4x100m freestyle quartet which was disqualified in the heats on the opening day.

Eight-time world champion Adam Peaty is not competing as he takes a break from the sport for mental health reasons.

Ledecky wins 20th world title

Elsewhere on day three, American Katie Ledecky claimed her 20th world title by winning the women’s 1500m freestyle.

Seven-time Olympic champion Ledecky, who won silver in the 400m freestyle on Sunday, secured her latest gold in a time of 15:26.27 – more than 17 seconds clear of Italy’s Simona Quadarella in second.

“It hurt a lot but I’m really happy with the outcome. I’m just having a lot of fun this week,” Ledecky, 26, said.

Australia’s Kaylee McKeown, who was disqualified from the women’s 200m individual medley on Monday, won the 100m backstroke gold in 57.53 seconds.

Lithuania’s Ruta Meilutyte, who won gold at the London Olympics 11 years ago, took the 100m breaststroke title in 1:04.62 to secure her first world triumph since 2013.

American Ryan Murphy touched first in 52.22 to snatch the 100m backstroke crown from Italy’s defending champion Thomas Ceccon.