Less than 24 hours after watching his side slump to a five-wicket defeat in the third Test against South Africa to lose the npower series, Vaughan called time on his 51-Test reign as captain.

Fighting back the tears at the National Performance Centre in Loughborough where he made the announcement, Vaughan finishes as the most successful England Test captain after 26 victories - and as the man whose team ended 18 years of failure to reclaim the Ashes in 2005.

But his struggle for form recently - he has scored only 40 runs in five innings during the series against South Africa - and the mental toll of attempting to lead a struggling side convinced Vaughan it was the right time to go.

The 33-year-old's announcement was quickly followed by the resignation of Paul Collingwood as one-day captain, with Kevin Pietersen expected to be announced as the new skipper of both sides during a press conference at Lord's tomorrow lunchtime.

"It's the hardest decision I've ever had to make, but also the easiest," Vaughan said.

"It's a job I've loved for five years and I've put my heart and soul into it.

"My mind told me to pack it in and I just felt if I kept on going my career could come to an abrupt end and hopefully this decision will prolong my career.

"I spoke to my dad this morning and he said, 'You can walk away a proud lad because you've given it everything and that is all I ever asked you to do'.

"I think this decision will prolong my career so hopefully this will make my last few years of playing a very exciting time and I can score a lot more runs.

"But I'm now in the ranks of all the other players and I need to score runs to get back in the team."

Vaughan has already ruled himself out of the final Test at the Oval, the squad for which will also be announced tomorrow, and intends to take a short break from the game before returning to play for Yorkshire.

He admitted he had hoped to carry on until next summer at least and have another crack at regaining the Ashes, but his recent struggles had persuaded him it was the time to walk away.

"It's a fairytale to captain your country and a real fairytale would have been to hold the urn again next year," Vaughan explained.

"But that is not to be and I know it is the right time to go because my mind is not working as well as my body.

"I've not been scoring the runs and that is because my mind hasn't been as fresh. There have been plenty of distractions as is the case with the captaincy, but over five years it has taken its toll.

"I've given it all I could and I wish I could have taken it on another year and one more stab at the Australians, but it is not meant to be - it's time to move forward with a new captain and in a new direction."

The new captain will have nine Tests - next week's finale to the series at the Oval, two Tests in India before Christmas, four Tests in West Indies in the new year and two at home to Sri Lanka at the start of next summer - before he leads out England for the start of the Ashes series in Cardiff on July 8, 2009.

It is a varied introduction to one of the most pressurised jobs in English sport and Vaughan, who became England's 74th Test captain when Nasser Hussain when he stepped down at Edgbaston five years ago, believes the new captain will need all of that time to become acclimatised to the role.

"Whoever gets the job will have about nine games to lead into the Ashes and that will be an experience, but what you get with a new captain is a real optimistic approach," Vaughan said.

"I'm looking forward to being the senior player. There'll be a bit of knowledge to pass on and I can continue to do that, I just won't be stood at mid on waving my arms around and moving fielders. It is a new chapter."

And Vaughan is certain the new captain should be given the job for both teams and allow the players to develop under one leader rather than under separate Test and one-day captains.

"I thought the split captaincy wouldn't work but it has in the way that we've had it with me and Paul Collingwood," he added.

"Results might not suggest that, but in the dressing room it has worked. In an ideal world I think one captain is the best for the team, one voice doing all forms of the game.

"That was when I was at my best because you're with the players all the time and you can really form a great bond.

"I'd already created that bond, but I think it would help the new guy if he did all forms of the game."