National team manager Chris Coleman said the 30-year-old did not want to join the squad because he was "psychologically disappointed" at only being put on standby.
The Wales boss was short of options at centre-half for Tuesday's 3-0 World Cup qualifying defeat by the Serbs at Cardiff City Stadium as Swansea skipper Ashley Williams was suspended and Sam Ricketts, of Wolves, injured.
Collins said: "Following reports in the media today I feel obliged to set the record straight as it has been wrongly suggested that I refused to play for my country against Serbia on the 10th Sept 2013.
"I would like to clarify that I was not contacted by Chris Coleman or anyone at the FAW (Football Association of Wales) to request that I join up with the squad for the Serbia game.
"Had I been asked I would have gladly joined up with my team-mates and represented my country.
"I did have a conversation with Chris to try to seek clarification on why I had been left out of the initial squad for both the Macedonia and the Serbia matches.
"But at no stage did I state that I would refuse to play for Wales.
"I am proud to come from Wales and even prouder to pull on the red shirt of my country so the suggestion that I would ever refuse to play for them is plainly wrong."