Ukrainian President Volodymyr Zelensky hopes to put Russia under such pressure by autumn that it will agree to an end to the war.
He told a gathering of Ukrainian ambassadors in Kiev on Monday that it was impossible to predict exactly when this would happen.
Ukrainian medium- and long-range drone strikes, international sanctions and diplomatic efforts must work together "to leave Russia with no alternative but peace", he said. "We will work very hard to make that happen this fall," he added.
At the same time, however, Zelensky was preparing for another winter of war. He tasked his country's diplomats with organizing the necessary technical support and weapons from foreign partners. "Every ambassador must secure weapons for Ukraine."
He cited the joint development of the Freyja missile defence system with European partners as an important international project for Ukraine.
Zelensky accused Russian President Vladimir Putin of delaying an end to the war and preparing for a further mobilization. Even after almost four and a half years of large-scale invasion, there are no signs that the Kremlin is backing down from its war aims, he said.
By contrast, many observers assume that the parliamentary elections in Russia in mid-September could be followed by a further wave of mobilization.
At the end of June, the Ukrainian President had announced a 40-day phase of intelligence operations aimed at persuading Russia to move towards peace.
This period included the spectacular attacks on logistics centres belonging to the Russian online retailer Wildberries. The 40 days come to an end on Tuesday.