LONDON -- Kalob Byers, the 28-year-old American citizen detained in Russia on drug smuggling charges earlier this month, has been released from detention, Kremlin spokesperson Dmitry Peskov told Russia's RBK news agency on Monday.

"We also expect that on Tuesday we will be able to talk about restoring the entire range of Russian-American relations," Peskov said. "Accordingly, certain events can be viewed in this context."

Byers' mother posted on social media on Sunday that she believed Kalob had already been released to the American Embassy in Moscow. She told ABC News that she believes he will be on a flight to the U.S. on Monday.

This is a developing story. Please check back for updates.

ABC News' Victoria Beaule and Joe Simonetti contributed to this report.