Manchester City have admitted they forget to notify the Football Association of Wales that Craig Bellamy would not be travelling with the squad to Montenegro.
Instead the striker is remaining at home after suffering a reaction to a knee injury following the victory against Celtic in a friendly on Saturday.
"Craig's situation should have been communicated to the Football Association of Wales over the weekend, but a misunderstanding on the process meant this was regrettably not done until today," the club said in a statement on Monday.
"Manchester City have now made contact with the Football Association of Wales to clarify the situation."
It continued: "Craig Bellamy is continuing his fitness and rehabilitation work following a knee injury.
"He suffered a reaction following Saturday's game against Celtic and is therefore unavailable to represent Wales in this week's friendly against Montenegro."
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