Fulham have an option to buy Warner at a pre agreed price before October 31st.
On the move Chris Coleman said
"Jaroslav Drobny picked up a knee problem in the States. He's had to have some minor surgery and will be out for six to eight weeks.
"Mark Crossley is doubtful for Saturday with a knee problem which has forced us to bring Tony Warner in from Cardiff. Tony started his career with Liverpool.
"He will be with us for a six-month loan-spell until January. Before then we'd expect Mark and Jaroslav to be back. Tony was training with us this morning. He's in great shape. I didn't realise how big he was until I met him. I'm pleased we've got him."
Good luck to Tony. His departure will fre funds to allow Dave Jones to be more agressive in his player search.
Martyn Margetson will step in as No'2 for City's game against Watford on Friday.