Villa are close to West Ham's ?8m valuation but Chelsea have the upper hand with their ploy to tempt Parker back to Stamford Bridge as temporary cover for Michael Essien, who could miss the entire season with a knee injury.
Loan ranger: West Ham are prepared to loan Scott Parker to Chelsea and bring him back if they get promoted to the Premier League next season
The loan option is favoured by West Ham, who like the idea that the Footballer of the Year will return to Upton Park if Sam Allardyce leads them back to the Barclays Premier League at the first attempt.
Parker is 30 with four years left on his contract and the Hammers are asking Chelsea for a loan fee of ?4.5million.
This figure is based on the fact that Tottenham charged their London neighbours a loan fee of ?1m to take Robbie Keane for six months and the assumption that Parker is in far better form than Keane.
Back to the Bridge: Parker cost Chelsea ?10m from Charlton in 2004 but was sold a year later to Newcastle
If Roman Abramovich agrees the loan fee, a deal could be done in time for Parker, currently in Switzerland with West Ham, to join Chelsea and fly out on their tour to the Far East on Sunday.
His wages of ?80,000 a week would not present a problem for Abramovich, coming in at half what John Terry and Fernando Torres earn, and the chance to compete for silverware and prove himself again in the Champions League appeals to the player.
West Ham co-owner David Sullivan admitted: 'A loan deal would appeal to us because we love Scott. We would obviously want a loan fee because he has substantial value and has three or four years left of his career.'
National duty: Parker harbours ambitions of playing for England at next summer's Euro 2012 championships
Andre Villas-Boas is a great admirer of Parker's industry and attitude, aview stemming from the year they worked together under Jose Mourinho.
Parker joined Chelsea for ?10m from Charlton in January 2004, when Claudio Ranieri was at the helm and played in the Champions League semi-final defeat to Monaco.
It turned sour when Ranieri was sacked and midfield opportunities became limited in Mourinho's 4-3-3 formation.
Number one: Parker could become Andre Villas-boas' first signing at Stamford Bridge with the new Chelsea manager looking for a replacement for injured Michael Essien
Parker broke a metatarsal bone in December and never played for the Blues again. He was sold to Newcastle the following summer for ?6.5m.
Tottenham and Arsenal have also monitored his situation since the Hammers were relegated but have failed to justify paying ?8m for someonewho will be 31 in October.
Aside from one dubious offer from Fenerbahce, lodged before the Turkish club was consumed by financial crisis, Villa are the first to made the first bid to sign Parker permanently.
Alex McLeish's team are boosted by funds from the sale of Ashley Young and the possible sale of Stewart Downing to Liverpool or Arsenal, although the Hammers are demanding the entire fee up front to minimise their losses after relegation.
In demand: Tottenham and Aston Villa have both registered an interest in the Hammers Player of the Year following West Ham's relegation in May
West Ham are close to signing Eidur Gudjohnsen and Irish midfielder JoeyO'Brien, a free agent who worked with Allardyce at Bolton, and agreeinga new deal with striker Zavon Hines, who is out of contract.
Villas-Boas, meanwhile, has found himself under verbal attack from Porto, where the club's charismatic president Jorge Nuno Pinto da Costa accused him of being scared off by 'Mourinho's ghost'.
Da Costa claimed the new Chelsea manager left the Portuguese champions because he could not live with the challenge of emulating Mourinho's historic Champions League triumph in 2004.
The 73-year-old Porto president said: 'He has a complex and is always thinking about the ghost of Mourinho and how Mourinho won the UEFA Cup and Champions League with Porto and he would not continue for fear of not earning it.'
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