German media outlet Kicker, as quoted by Metro, is reporting that the Bundesliga don’t want the transfer to go through until the next financial year.
The same article states that Dortmund will force Arsenal to wait until 1 July at the earliest before the Gunners can announce the Greece international as their second summer signing.
Unai Emery will take his Arsenal team to Singapore on 2 July to take on Atletico Madrid and Paris Saint-Germain on their pre-season tour.
The Gunners signed Switzerland international Stephan Lichtsteiner on a free transfer from Serie A giants Juventus last week to bolster their defensive options.
Arsenal have also been linked with a move to sign Manchester United midfielder Marouane Fellaini on a free transfer to add more steel to their midfield.
The north London side finished in sixth place in the Premier League table to miss out on Champions League football for the second successive season.
Arsenal haven’t won the Premier League title 2003-04 and have regressed under Arsene Wenger over the past decade or so.
The Gunners lost to Manchester City in the League Cup final last term.
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