OTTIS GIBSON has decided to step down as England bowling coach to take over as the head coach of South Africa.

Gibson, who began his second stint with England in early 2015, will leave his post at the end of the Test series against West Indies.

"I would like to place on record my thanks to Ottis Gibson for his services to English cricket," said England and Wales Cricket Board director Andrew Strauss.

"Ottis has been an integral part of the England team in his two stints as bowling coach.

"His experience, tactical awareness and understanding of bowling in all conditions has benefited our approach and has helped our bowling unit develop greatly across all formats of the game.

"He is an ambitious man and when this opportunity presented itself it was difficult for him to turn down.

"On behalf of the ECB, I would like to wish him every success in the next chapter of his career."

Gibson's decision leaves England searching for a new fast bowling coach ahead of the Ashes in Australia, which begins in November.

"Ottis has played a vital role in our progress over the past few years," said England head coach Trevor Bayliss.

"His knowledge of the international game and the way he has supported all our bowlers in their development has been immeasurable."

Meanwhile, Tom Westley has been spared the axe as England named an unchanged 13-man squad for the third Test decider against West Indies at Lord's next week.

Westley's place has come under scrutiny following three single-figure scores in the Investec series as he has struggled to convince that he is the long-term solution to the problem number three position in the batting order.

But, in their final Test before this winter's Ashes, England have decided to keep faith with the Essex batsman and it seems he will be given another opportunity to press his claims for the trip to Australia.

Squad: J Root (captain), M Ali, J Anderson, J Bairstow, S Broad, A Cook, M Crane, D Malan, T Roland-Jones, B Stokes, M Stoneman, T Westley, C Woakes.