Russian President Vladimir Putin, right, and Serbian Deputy Prime Minister Aleksandar Vulin pose for a photo on the sidelines of the Eastern Economic Forum in Vladivostok, Russia, Wednesday, Sept. 4, 2024. (Kristina Kormilitsyna, Sputnik, Kremlin Pool Photo via AP)

Serbian Deputy Prime Minister Aleksandar Vulin listens to Russian President Vladimir Putin during their meeting on the sidelines of the Eastern Economic Forum in Vladivostok, Russia, on Wednesday, Sept. 4, 2024. (Kristina Kormilitsyna, Sputnik, Kremlin Pool Photo via AP)

Russian President Vladimir Putin, right, speaks to Serbian Deputy Prime Minister Aleksandar Vulin during their meeting on the sidelines of the Eastern Economic Forum in Vladivostok, Russia Wednesday, Sept. 4, 2024. (Kristina Kormilitsyna, Sputnik, Kremlin Pool Photo via AP)

Russian President Vladimir Putin, right, and Serbian Deputy Prime Minister Aleksandar Vulin talk to each other during their meeting on the sidelines of the Eastern Economic Forum in Vladivostok, Russia, on Wednesday, Sept. 4, 2024. (Kristina Kormilitsyna, Sputnik, Kremlin Pool Photo via AP)