The American has said it would be "ludicrous" for Liverpool to allow the Uruguay striker to join a rival Premier League club and stressed it was too late in the transfer window to seek a replacement.
Suarez has made no secret of his desire to leave Anfield, hoping to join a club that can offer him Champions League football.
But Henry has now stressed he will have to stay with Liverpool and join their push for a top-four finish next season.
Henry said, according to the Liverpool Echo newspaper: "We are not going to sell Luis.
"He is one of the best players in the world. I have no reason to believe that he won't continue to be.
"The club is headed in the right direction and this episode is not going to stop us. It is what we are all focused on right now."
Liverpool's target is the elite level of European football, and captain Steven Gerrard has said recently that Suarez holds the key to how the club will perform in the new campaign.
Henry knows the significance of Champions League football, which as well as offering the prospect of challenging for a trophy Liverpool have won five times also offers huge financial benefits.
Henry said: "I think for all of the top clubs it's extremely important. Especially for Liverpool, since we have not been in Europe and are not in Europe this year - and we haven't been in the Champions League for a while - obviously to sell Luis to a rival for one of those positions would be ludicrous.
"I have told Ivan Gazidis that Luis is not for sale. I am unequivocal on that."
Henry stressed Arsenal would be wasting their time with another offer for Suarez, having had an offer of £40million plus £1 rejected.
The suggestion from the Suarez camp that such an offer should trigger a clause allowing him to leave has been dismissed out of hand by Liverpool.
And Henry ruled out granting the 26-year-old his wish to join Arsenal, or any other side.
Henry said: "Luis Suarez is a Liverpool player come what may."
He stressed Liverpool were simply not in a position to allow their most potent goalscorer to depart, with the Barclays Premier League season beginning on Saturday week and the club determined to improve significantly on last season's seventh-placed finish.
"It's not finances, it is football. That's why I said at this point, this late in the window, everyone has already moved and we haven't identified anyone who hasn't already moved - or isn't moving - to replace him," Henry said.
"So it's for football reasons and especially not to Arsenal. I think we made that clear early on."