Arsene Wenger has admitted he hopes Arsenal's signing of Shkodran Mustafi "will be done" before the transfer deadline.
Sky Germany reported in July that the Gunners had opened talks with Valencia to make the Germany international their new defensive signing.
Sky sources reported earlier this month that Mustafi had subsequently agreed to the move, with negotiations ongoing over the transfer fee. Mustafi is valued at around £30m but it is understood Arsenal are trying to negotiate less.
Wenger was once again forced into a staunch defence of his transfer policy on Saturday after calls from supporters to spend money following the 0-0 draw at Leicester
And he told French TV station SFR Sport: "Mustafi? We hope it will be done He is one of a number of players we are looking at. Negotiations are ongoing."
Arsenal have had issues at centre-back since a long-term injury to Per Mertersacker ruled him out until the New Year and Gabriel Paulista is also ruled out for six weeks.
They signed 20-year-old Englishman Rob Holding from Bolton and Wenger praised his performance at the King Power Stadium, while Poland youngster Krystian Bielik is also being developed as a centre-back.
But they want to add another experienced defender and former Everton defender Mustafi has been with Valencia since 2014, when he transferred from Sampdoria, and has made over 60 La Liga appearances.