Saul was on loan last season.Chelsea aren't really in a position where they can allow one of their most sellable assets to go on loan for nothing, especially as there would be plenty of clubs willing to pay decent money for him.
They have a lot of work to do on their squad and no longer have a bottomless pit of free money to fund it. They've already lost Rudiger, Christensen & Saul for nothing - and have Alonso, Kante, Jorginho, Azpilicueta & Thiago Silva the wrong side of 30 with one year left on their contracts.
The idea that they would give Inter a bucket load of cash PLUS a player they bought for £100 million just 12 months ago doesn't seem to make much sense.