Bundesliga giant Dortmund confirmed the agreement on Thursday (AEST), meaning the 28-year-old will spend his second successive season away from the club.

Schurrle made 24 Premier League appearances for Fulham last season, scoring six goals.

Spartak have the option to sign the former Bayer Leverkusen, Chelsea and Wolfsburg player permanently next year, with the fee reportedly set at €6million.

Schurrle broke through at Mainz before his form with Leverkusen alerted the attention of Chelsea.

Jose Mourinho made Schurrle the first signing of his second stint at the club for a reported fee of £18m in 2013.

The attacker made 44 Premier League appearances for Chelsea before returning to Germany with Wolfsburg in 2015, though things have not really worked out since a subsequent move to Dortmund a year later.

He has played in 33 Bundesliga matches for Dortmund, scoring three goals.

Schurrle's arrival will boost a Spartak side sitting 10th in the Russian Premier League after three matches.