The Spaniard, who has come under fire after Liverpool's shaky start to the season, also defended his transfer dealings and said he had put the club back on the world map since taking over five years ago.
"I'm confident it will never happen," Benitez said in a wide-ranging interview in The Times on Tuesday, when asked whether he would ever sanction the sale of Torres to pay off some of the club's debts.
"If it did, I'd resign."
Highly-rated Dutch winger Ryan Babel, another Benitez signing, has struggled to make an impact as have the likes of David N'gog and Lucas Leiva.
"We can only buy one or two big, 20 million pound players a year," Benitez said. "If we want to have money available, then we have to sell some players. We have to sell expensive and buy as cheaply as possible.
"Aquilani fit would be 20-30 million. We checked with doctors and they said he would be out one, maybe two months. We have lost some time, but I signed the player for five years, not five weeks. We needed to take the risk.
"Ryan (Babel) was signed for the future and we are waiting for his improvement. He has to be more consistent."
"He put in a transfer request," Benitez said. "We had a professional and good relationship."
Despite Liverpool's title challenge already evaporating, Benitez said it was not all doom and gloom.
"People are worried," he said. "But the team will improve. When we have key players on the pitch we are as good as anyone. We have proved this in the past.
"There is a massive difference between five years ago and now," Benitez said. "The name of the club round the world is at the same level as it was in the 1980s. It's a fantastic achievement. Everybody talks about Liverpool in a good way. And we will get better.
"In 2004 the squad was worth, what, 100 million? Now perhaps we have one player worth that. The whole squad? Maybe 250 million. We must be doing something right."
