Alexander-Arnold was not picked by Gareth Southgate for the Three Lions’ World Cup qualifiers games against San Marino, Albania and Poland.
The Liverpool-born star has been ever-present in the England squad since he rose to prominence at Anfield. Having made his international debut in June 2018 against Costa Rica, the 22-year-old has since won twelve caps in total for his nation.
Alexander-Arnold’s form seems to have dipped in recent weeks and does not emit his known standards anymore.
Ahead of the Reds’ trip to face Arsenal in the Premier League on Saturday, Klopp has admitted he did not understand why Alexander-Arnold was left out from the England squad.
"I was surprised when he didn't get the call-up. I respect the decision, of course I do. But I didn't understand it,” the former Borussia Dortmund coach said.
"I am a manager myself, I make decisions every day, every weekend, every midweek about team selections and squad selections.
"We always make decisions that other people probably do not understand.
"If Trent Alexander-Arnold is not in the squad of England then England must have an extremely good squad, let me say it like this.
"I have no problem if my players get some criticism. They can get it from me, they can get it from other people.
"I respect that Gareth makes his own decisions, of course, but I didn't understand it anyway because Trent Alexander-Arnold was in the last two seasons at least, let me say the season before and the season before that, the stand out right-back in world football - that is the truth and at an unbelievable young age.
"He started the season with Covid and you can imagine it took him a while to get into the season, but from the moment when he was in the season he was one of our most consistent players and a stand-out player.
"He could play all the time, high level all these types of things, so that cannot be the reason that he was not in the squad.
"If you compare Lionel Messi every year with his best season ever then he is not performing now like he was performing in 2005 and 2006 maybe but he is still the world's best player."