Sead Kolasinac has agreed to join Bundesliga side Schalke on loan for the remainder of the season, Arsenal have announced. The Bosnia defender will head back to the club where he joined the youth set-up and went on to become a first-team regular before moving to the Gunners during June 2017. Earlier on Thursday, Arsenal manager Mikel Arteta confirmed the club's priority for the January transfer window was to trim down the size of the current squad. Kolasinac's last appearance for the Gunners was in the 4-1 League Cup defeat by Manchester City on December 22. During November, the 27-year-old had spent a period of self-isolation after the Bosnia and Herzegovina Football confirmed the defender has tested positive for Covid-19 while away on international duty. Kolasinac's loan move is set to begin on January 4, with the full-back having made 113 appearances for Arsenal, helping the team reach the 2019 Europa League final against Chelsea. Arsenal technical director Edu said on the club website: "Sead needs to be playing regularly, so we have decided together that a move back to Germany with Schalke will benefit him at this moment. "We will be keeping in close contact with Sead, and wish him huge success for the remainder of the season with Schalke." Meanwhile, Arteta said the club's priority is to streamline the bloated squad in January. The Gunners were able to offload Emiliano Martinez and Henrikh Mkhitaryan in the summer window while Matteo Guendouzi and Lucas Torreira departed on loan. But forgotten man Mesut Ozil remained at the Emirates along with Shkodran Mustafi. The club have been linked with a loan move for Real Madrid playmaker Isco in January but first of all technical director Edu will attempt to raise funds by moving on those who are surplus to requirements. "There are some players that are going to go on loan and going to leave and that is the priority at the moment," Arteta said . "We cannot sustain the numbers that we have in certain positions and we are looking to do that, and then we will see if we have the right opportunity in the positions where we need some more help." ________________________________________________