Charlton were keen to keep Mills

Mills, who is on loan from Manchester City until the new year, was dismissed for using foul and abusive language.

"We have been discussing the situation with City in terms of keeping Danny," said Charlton manager Alan Pardew.

"We need to absorb what happened here on the back of that. It's difficult to reflect now. He will miss three games, so we have a big decision to make."

Mills was sent off after reacting angrily following a clash with Hull striker Caleb Folan.