Press Association Sport understands Villa are hoping to receive around £3million for Cuellar, who joined them from the Gers three years ago for nearly £8million.
The Scottish giants have been told their current offer of £1.5 million is not high enough.
Cuellar is currently sidelined after undergoing knee surgery at the end of last season.
But this has not put off new Rangers boss Ally McCoist, who worked with Cuellar during his previous spell at Ibrox.
Villa are also unlikely to sign midfielder Michael Bradley on a permanent basis from Borussia Monchengladbach.
The United States international made only a minimal impact when on loan at Villa during the second half of last season.
Source: PA
Source: PA