Worcestershire are considering "other options" to fill their overseas player slot with Phil Hughes likely to be in Australia's Ashes squad.
The Royals were hoping the opener would return to New Road this season but Hughes is unlikely to be available for much of the summer following his successful return to the Australia Test and one-day team.
Worcestershire could still sign him for the early part of the 2013 county season but chief executive David Leatherdale admits they may have to go back to the drawing board.
"Phil is still on our agenda and at the moment is available in April and May even if selected for one-day and Test cricket," he said.
"But we are looking at other options and Phil is aware of that and hopefully something will be sorted by next week.
"We would like Phil although the difficulty is knowing whether Australia will put in place training camps before the Ashes tour which would obviously limit the availability.
"Phil knows we would like someone for a longer period. But, if Phil is available and we cannot sign anyone who is available for longer, then we would happily welcome him back if possible.
"He did very well for us last summer, he has said himself he would like to come back, and has been in good form since getting back into the Australian side."