Since arriving at Selhurst Park on a short-term loan deal, Sakho has played a pivotal role in Crystal Palace's fight for survival.
In the six games Sakho has played, Palace have won five, including a 2-1 win over Chelsea, and kept four clean sheets.
Jurgen Klopp stamped down on Sakho's ill-discipline during pre-season last summer by refusing to name him in any of Liverpool's first-team squads this term.
Crystal Palace have made no secret of their hopes to sign Mamadou Sakho permanently
Sam Allardyce said Crystal Palace simply didn't have time to haggle for a option to buy clause
The Liverpool boss has remained coy on whether Sakho still has a chance to redeem himself at Anfield.
And Palace have made no secret of their hopes of acquiring the French defender in the summer.
But Allardyce has revealed why Palace couldn't include the option to buy Sakho at the end of his loan deal.
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“There isn't a clause because his deal was done in the Bournemouth corridor after we had won 2-0 by me and Steve finishing the negotiation over the phone to try and secure Mama and now, what a great deal that was," Allardyce said.
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"It was a negotiation on the final day – it was just about getting it done, getting the loan deal done, not haggling about other things other than just making sure we get him here.
"At the moment that has paid off for us. What happens in the summer can only happen in the summer and can only be talked about for me when we are safe.
"We are not safe and can't talk about Mama Sakho being a permanent deal here because we are still not safe and our position in the PL is not safe.”