(ANSA) - BELGRADE, AUG 8 - "I just finished a long conversation with Ukrainian President Volodymyr Zelensky about the situation in Ukraine. There are certain signs, and perhaps even a hunch, that a cease-fire in the conflict is closer than it appears," Polish Prime Minister Donald Tusk said, according to the PAP news agency. Zelensky is "very cautious, but still optimistic," Tusk added, noting that Donald Trump's ultimatum to Vladimir Putin to stop attacking Ukraine and avoid secondary sanctions expires today. (ANSA).