David Beckham has announced the end of his glittering career 21 years after making his debut for Manchester United. His last game will be Paris Saint-Germain's trip to Lorient next weekend.

After rejecting a fresh contract at PSG, the former England captain will step down at 38 having become the world's most recognisable player and a global brand whose commercial interests helped amass a fortune worth over £165m.

Beckham will retire having won 19 major trophies, which include league titles in four different countries and the Champions League. He played for six clubs in England, Spain, Italy, America and France, was awarded 115 caps and is the only England player to score at three World Cups.

Beckham admitted to uncertainty regarding the decision. "Over the years, when I've seen players retire, when you ask them about it, they always say you'll know when you're ready. I think I'm ready," he said. "It's a difficult decision, because I still feel that I can play at the top level, and still have done for the last six months.

"But I always secretly said to myself that I want to go out at the top. And if you'd have said to me eight months ago I'd be playing in the French league, winning the French Cup – winning the league – and finishing like this, I would have probably said, absolutely no chance. But I was given the opportunity to come to PSG and I just feel now is the right time.

"I love the game so much. I just feel that … I don't know. It's the right time. I believe it's the right time. But I'll always feel that I can do more, that's the problem."

Beckham joined PSG in January after a five-year spell at Los Angeles Galaxy during which time he helped football expand in the United States. As well as helping PSG to win the French championship, he played for them in the Champions League quarter-finals against Barcelona during 11 appearances that included being sent off.

Asked when he knew it was time to retire, Beckham said jokingly: "Probably when [Lionel] Messi was running past me in that home game. No, I actually don't know. I just feel that I've been so lucky throughout my career. I feel that the fact that I've played for the clubs that I've played for, the players that I've played with, won the trophies that I've won.

"Playing in the MLS last year, winning the championship there and then coming to PSG and winning the French league. It's a good way to go out. It's every athlete's dream, every footballer's dream – to go out on the top. On top form, or winning a trophy. It doesn't happen that often. I've been lucky. When I left United we won the league. When I left Madrid we won the league [2007]. It's nice to go out like that. You're leaving as a champion."

Beckham recovered from public opprobrium after being sent off against Argentina at the 1998 World Cup for kicking out at Diego Simeone in time to enjoy a supremely successful club and international career, though he failed to win any honours for England.

Beckham's stay at United ended under a cloud in 2003 after Sir Alex Ferguson, the manager, lost patience with an off-field profile boosted by marrying Victoria Adams, a Spice Girl, and a growing array of commercial deals.

Yet despite continuing to develop Brand Beckham, which included being a London 2012 ambassador, he wants to be remembered for his playing achievements. "I just want people to see me as a hard-working footballer. Someone that's passionate about the game," he said on Sky Sports News.

"People have looked at certain other things that have gone on throughout my career, and sometimes that's overshadowed what I've done on the pitch. As much as I say that doesn't hurt me, of course it does. I'm a footballer who has played at some of the biggest clubs in the world. I played for my country 115 times, been runner-up twice as World Player of the Year to two amazing footballers. I'm very proud."

Now that he has decided to stop playing, Beckham will be in demand from within football and beyond. Nasser al-Khelaifi, the PSG president, said: "We are discussing the possibilities to keep working together at Paris Saint-Germain."

Beckham is expected to return to London with Victoria and their four children. He has suggested he would like to invest in an MLS club and pursue his youth coaching schemes.