Coutinho is a transfer target for Barcelona and a £72million bid has been made and promptly rejected by Liverpool.
The Brazilian signed five-year contract keeping him at Anfield until 2022 in January with Klopp intending to make him the central hub of the team.
Liverpool's hierarchy have also backed the decision to not sell Coutinho.
And in his pre-Audi Cup press conference in Munich today, Klopp once again reiterated Coutinho would remain at Anfield.
"There is no other way to interpret it - he is not available to be sold," Klopp said.
"The word 'not' means there is no interpretation for that. It's nothing new, is it?"
Liverpool are set to face Bayern Munich on Tuesday then Atletico Madrid or Napoli on Wednesday.
Klopp confirmed Loris Karius, Dejan Lovren and James Milner will all be available for selection for the friendlies but Nathaniel Clyne (back) and Danny Ward (back) are sidelined and face a race to be fit before the start of the season.
The Liverpool manager also asked for patience with Danny Ings as he continues his recovery from a knee injury.
“He is in a really good way and we are very pleased with what he is doing,” said Klopp.
“But it is smart and responsible for him that we allow him maximum time and sessions – both individually and with the team.
“So maybe not involved in the matches just yet but that means nothing more than we take our time and make him strong and ready to be a part of what we are going to do.”
Source: Daily Express