The Daily Mail says Lovren has been unable to join his new Liverpool team-mates in the U.S. after failing to obtain a visa in time.
The centre-back, who joined the Reds in a £20million move from Southampton, attended the U.S. embassy in London but was unable to obtain the mandatory visa before Liverpool head home from the States next week.
Speaking to Sportske Novosti, Lovren said: "Unfortunately I could not get a visa straight away.
"Therefore I can not join my team-mates in the U.S. I am sad because of that.
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