The Reds not on international duty returned from a short break to prepare for a visit to the Emirates this weekend, with Roberto Firmino back from injury.
Naby Keita was also involved, having been recalled from the Guinea squad early, while Klopp retained a clutch of the academy players initially called up earlier in the month when numbers were short.
There was no sign of Melkamu Frauendorf, Tyler Morton, Conor Bradley or Kaide Gordon, who were involved at the start of the international break, while Jarell Quansah, James Norris and James Balagizi were unavailable.
Ready for the week ahead ?? pic.twitter.com/vCj6DYwqLp
Klopp led a rousing rendition of Happy Birthday for elite development coach Vitor Matos, who turned 32 on Sunday, before the squad split off for drills, rondos and small-sided games.
Along with Firmino and Keita, Alisson was part of the senior cohort, and the Brazilian was sporting an impressive moustache, joking with Klopp that he looked like Ian Rush:
"More like @Ian_Rush9…"
James Milner has worked at Kirkby throughout the break, with the squad given the option to either stay at the training ground or follow individual programmes from home, and the vice-captain clearly relished the return to action:
Tuesday brings the penultimate day of internationals, with Gini Wijnaldum, Diogo Jota, Ozan Kabak, Sadio Mane and Neco Williams all in action, before Thiago, Andy Robertson, Curtis Jones, Xherdan Shaqiri and Kostas Tsimikas conclude the break on Wednesday.
Liverpool squad in training on Monday
Defenders: Phillips, R.Williams, B.Davies, Koumetio, Alexander-Arnold, Beck
Midfielders: Fabinho, Keita, Milner, Oxlade-Chamberlain, Woodburn, Cain, Clarkson
Forwards: Firmino, Musialowski