Allardyce accepts the Hammers have to look at balancing the books after their relegation from the Barclays Premier League last season but stressed players would not be allowed to leave cheaply.
"I believe at this stage that the offer is not good enough. It is not to the club's valuation," the West Ham boss told The Sentinel.
"We are keen to keep our key players. However, we have lost our Premier League status and our financial position has to be addressed.
"A part of that might be players are sold back to the Premier League, but only so long as that is right for our club."