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He will then attend the football tournament's inaugural match on Thursday, pitting Russia against his longtime backer, Saudi Arabia.
Riyadh has been a key ally of Hariri for years, but the relationship appeared to falter in late 2017 when Hariri announced his surprise resignation during a trip to the kingdom.
He subsequently rescinded the decision and in May was appointed for a new term as prime minister following parliamentary elections.
He is now in talks to form a coalition government.
Hariri, 48, met Putin in the Russian Black Sea resort of Sochi in September 2017.