Arsenal have lost out in the race for Borussia Monchengladbach's Marco Reus, with the forward set to re-join Borussia Dortmund at the end of the season.

Reus, 22, has been one of the Bundesliga's stand-out performers this season and will bolster Dortmund's strike-force when he joins on a €17.5million (£14.5m), five-year contract in June.

The capture of Reus, who came through Dortmund's youth academy before being sold in 2006, represents a major coup for the defending champions and comes as a bitter blow to Arsenal's hopes of easing the goalscoring burden on Robin van Persie.

"It's important for me to clarify that this wasn't a decision against [Borussia Monchengladbach]," Reus said.

"I've had a wonderful time here up until now and Borussia gave me the chance to prove myself in the Bundesliga and to develop into the player I am now.

"I'll be sad to leave, as it's been such an important environment for me. It was crucial for me to be upfront and honest with Gladbach and not to drag it out."

Arsenal manager Arsene Wenger has admitted in the past that he is a keen admirer of the German international and the Frenchman could now step up his pursuit of Reus' Dortmund team-mate Mario Gotze, as he seeks a long-term replacement for Cesc Fabregas.

However, Dortmund sporting director Michael Zorc has publicly revealed the 19-year-old German international is not for sale and the club is prepared to rebuff any offers that arrive in January or the summer.

"We agree with Mario that he plays next season in Dortmund. Gotze has a contract until 2014 - we have no reason to sell him," Zorc told German newspaper Bild.

"But I am not a prophet. If tomorrow someone offers one billion euros, then you should think about it."