The 19-goal Argentinian still has 18 months left on his contract at Leeds, but has been linked with both Wigan and Hull in recent weeks and Warnock feels the mounting speculation has had a negative affect on the 29-year-old, who is in his fifth season with the club.
"I've spoken to him but there's only so much you can say," Warnock said. "No doubt we'll be speaking over the next 10 days to him or his agent.
"I think you haven't got to think about hypothetical things. We want Luciano to stay and that's our prerogative and he's got 18 months left.
"We're not the ones turning his head so we'll have to wait and see what his head's like. That's the answer - on the field of play. Only the next couple of weeks will tell us.
"Once the deadline's gone I'm not bothered because he'll get down to it and be back to normal. It's just that the heads get turned and you can't stop that. It's a nightmare scenario."
Warnock hinted he could be tempted to leave Becchio out of his starting line-up against bottom club Bristol City after he missed the midweek FA Cup replay win at Birmingham through illness.
He added: "Because we have Luciano at times, players tend to hit the longer ball. We didn't have him on Tuesday so we wanted to play more. We had to play it into Ross (McCormack)'s feet more and yet we did have the threat. We had a good balance so it'll be interesting to see what we do if Becchio's fit.
"If we play well, we don't always hit the long ball. We play some good football. When you're not playing well, you don't want to give the ball away so you automatically play it well. But the other night was out of defence, through midfield. It was good.
"You have to look at whoever's fully fit and if Luciano's fully fit, it's a brave man who leaves a 19-goal striker out."
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