Sounds to me that he made a gentleman's agreement with Ayre and Rogers and they deliberately gave him a badly written contract as a backdoor to avoid his departure:
The Guardian wrote:The bid, though, tested the clause and revealed that Liverpool saw £40m as the point at which they must start to negotiate, not the point at which they are obliged to sell.
There is no sense in including a clause that says "you are forced to negotiate". So what? It has no practical consequences. It imposes no burden on the club at all (their negotiation could well be sending the gardener with instructions to say "no" to very offer). If I'm forced to negotiate but not to reach an agreement, I might just save the negotiation at all. It's simply ridiculous from a legal point of view.
I'm inclined to believe Suarez here. There's probably the +40M clause in the contract but it's so badly written that 'Pool are hanging on to a straw and hope Arsenal won't test it on court, or can get more coin by negotiating an "amicable" solution.