Calderwood represented England in 2005 and 2006
Winger Mark Calderwood has been added to England's World Cup train-on squad, despite having been called up for the tournament by Scotland.
Calderwood, who was joined in England's squad by Wigan's Stuart Fielden, Mickey Higham and Gareth Hock, has subsequently been released by Scotland.
He has represented England before but has a Scottish grandparent.
The Rugby Football League said no rules were broken and the decision was Calderwood's to make.
The 26-year-old could benefit from the injury-enforced withdrawal of Hull FC winger Gareth Raynor from the England squad, but there is no guarantee he will definitely make the final squad.
Scotland have removed Calderwood, who will join Hull FC next season, from their squad, raising the prospect of the winger missing out on the tournament altogether.
"Put simply we are only interested in players that want to play for Scotland," said Scotland manager Richard Thewlis.
"We will not be waiting to see if he makes the England side - he has made his choice and is now out of our considerations."
England also brought Salford scrum-half Richard Myler, 18, into the squad.
Myler, the National League One Young Player of the Year, is the only non-Super League player chosen in England coach Tony Smith's squad.
The youngster is thought unlikely to make the final 24-man World Cup squad, but he is set to play in England's World Cup warm-up match against Wales at Doncaster on 10 October.
Smith will name his final 24-man England squad on Tuesday, 7 October.
Winger Calderwood, prop Fielden, hooker Higham and second rower Hock all played a key role in Wigan's play-off charge, which was eventually ended by Leeds.
Smith, who will add players from St Helens and Leeds after Saturday's Grand Final, has indicated several squad places have yet to be settled.
"There are some firm favourites to make the squad but there are half a dozen spots still up for grabs," he said.
England begin their World Cup campaign in Australia with a pool game against Papua New Guinea on 25 October.