The Reds boarded a flight to California in the early hours of Thursday morning, directly following their 2-0 victory away to Huddersfield Town.
The German has taken a strong squad for the trio of warmup fixtures, with George, Alexander-Arnold and Ejaria representing the club’s academy.
Sixteen-year-old forward Ben Woodburn, however, is expected to have been left out.
Klopp’s squad will be joined by the rest of Milner’s England colleagues from the summer’s European Championship, with Nathaniel Clyne, Jordan Henderson, Adam Lallana and Daniel Sturridge already in the US.
They will be followed by the arrivals of Simon Mignolet, Divock Origi, Christian Benteke and Emre Can, while Georginio Wijnaldum is expected to link up with his new team-mates on the completion of his £25 million move from Newcastle United.
One player who hasn’t travelled is Jon Flanagan, with the full-back mulling over a season-long loan move to Burnley, while Joe Allen isn’t expected to join the squad on his return from a summer break.
Tiago Ilori is also unavailable, having joined the Portugal squad for training ahead of this summer’s Olympic Games.
Liverpool US Tour Squad (TBC): Karius, Mignolet, Manninger, George; Lovren, Matip, Klavan, Wisdom, Sakho*, Gomez*, Clyne, Randall, Alexander-Arnold, Moreno, Smith; Lucas*, Grujic, Can, Henderson, Milner, Brannagan, Stewart; Ejaria, Lallana, Markovic, Mane, Coutinho, Ojo, Wijnaldum*; Firmino, Ings, Sturridge, Origi, Benteke
(* – Injured, or yet to be signed)