Celtic are reportedly braced for a new West Ham bid for Arne Engels.
It's claimed the Championship side are set to test the resolve of Parkhead chiefs with a return to the negotiating table this week.
According to The Scottish Sun, West Ham are expected to come in with a third bid for the midfielder this summer.
And after selling £10m for the sale of Freddie Potts to Club Brugge, West Ham are in a position to make an improved offer for Engels.
Celtic booted out a £25m bid for Engels in January, with reports suggesting it'd take a bid in a similar region for a transfer to be agreed this summer.
However, Martin O'Neill wants to keep the key Belgian midfielder, 22, for the Champions League play-off against LASK later this month.
On keeping hold of Engels and Alistair Johnston, who is wanted by Everton, for the qualifiers, O'Neill said: "Ideally that would be brilliant. That would be really good. One wouldn't know whether the clubs then, the other clubs, would want to pursue that if that was the case.
"I'm quite sure that anybody starting off in their own particular leagues would want their players in as soon as possible. But ideally that would be great."
