Everton have rejected an enquiry from Sunderland to include Phil Jagielka as part of a deal for Lamine Kone.
Sources told ESPN FC on Tuesday that Everton are in advanced talks with Sunderland defender Kone, who is wanted as a replacement for John Stones.
Everton have already agreed a deal for Swansea and Wales captain Ashley Williams and Toffees boss Ronald Koeman hopes to also bring in Kone to strengthen his defensive options.
The arrivals of Williams and Kone would increase competition for places in Everton's defence and Sunderland have made an enquiry about Jagielka's availability.
New Sunderland boss David Moyes signed Jagielka from Sheffield United in 2007 when he was in charge of Everton and he is keen to be reunited with his former captain.
However, Everton have rejected Sunderland's approach to have the England international in part-exchange as any deal for Kone, who is now expected to return to training with Sunderland with his proposed move to Everton yet to be completed.