Victoria Beckham has spoken candidly about her husband David's highly-publicised alleged affair, describing it as the "hardest period" of their marriage.

The couple have previously denied claims that he had an affair while playing for Real Madrid in 2003.

"It was the hardest period for us because it felt like the world was against us," the former Spice Girl said in a new Netflix documentary.

"Here's the thing - we were against each other if I'm completely honest."

In the documentary, titled Beckham, which was released on Wednesday, the couple don't discuss the details of what happened.

But Victoria said: "You know, up until Madrid, sometimes it felt like us against everybody else. But we were together, we were connected, we had each other.

"But when we were in Spain, it didn't really feel like we had each other either. And that's sad."

She continued: "I can't even begin to tell you how hard it was and how it affected me."

Speaking about the press attention after she and the children then moved to join her husband in Spain, she added: "It was a nightmare. From the minute we opened the press were there in cars and everywhere we went, we were followed.

"It was an absolute circus - it's really entertaining when the circus comes to town right? Unless you're in it."

When the singer-turned-designer was asked if she had resented her husband at that time, she replied: "If I'm being totally honest, yes I did.

"It was probably, if I'm being honest, the most unhappy I have ever been in my entire life."

In the series, the ex-England and Manchester United midfielder - now owner of Inter Miami - also addressed how the speculation around his extra-marital affairs affected him and his family.

"There was some horrible stories that were difficult to deal with," he said. "It was the first time that me and Victoria had been put under that kind of pressure in our marriage.

"I think we both felt at the time that we were, not losing each other, but drowning."

He added: "I don't know how we got through it, in all honesty."

'Keep it vague'

The Independent's review of the docuseries pointed out that its makers "keep it vague" when talking about David's alleged infidelities.

The paper's four-star review said: "Posh and Becks are happy to talk about anything from fights with Fergie, crude chants, THAT red card, sarongs and matching purple wedding outfits, but director Fisher Stevens stays friendly on trickier topics."

The Guardian also awarded four stars, describing the docuseries as a "candid, riveting truth about the footballer's life".

"This absolutely star-packed docuseries is a fun, gossipy watch full of blunt, entertaining interviews," wrote Rebecca Nicholson. "Every episode just flies by."

The Telegraph went one better, awarding full marks for a "superb, intimate and at times heartbreaking portrayal of an unexpectedly complex man".

"Beckham eschews the trend for sports documentaries that serve as nothing more than PR exercises, charting David's career and family life," the paper's Benji Wilson wrote.

The Beckhams, who married in 1999, and their four children turned out for the London premiere of the series on Tuesday.