The war in Ukraine began with Crimea and must end with its liberation, President Volodymyr Zelensky has said.
Ukraine’s president was speaking after a string of explosions hit a Russian airbase there, killing one person.
Mr Zelensky did not mention Tuesday’s blasts but said: “Crimea is Ukrainian and we will never give it up.”
Russia’s defence ministry said ammunition detonated at the base. Meanwhile, Ukraine denied any responsibility for the explosions.
In a separate development, Ukrainian officials say 13 people were killed in overnight Russian strikes in the central Dnipropetrovsk region, and another one in the Zaporizhzhia region in the south.
Crimea is internationally recognised as part of Ukraine but the Black Sea peninsula was annexed by Russia in 2014 after a referendum which the global community sees as illegitimate. Many Ukrainians see this as the start of their war with Russia.
On Tuesday, a series of explosions rocked the Saky military base near Novofedorivka, in the west of Crimea which is near seaside resorts popular with Russian tourists.
Novofedorivka and Saky are about 50km north of the port of Sevastopol, home of Russia’s Black Sea Fleet, which has been leading a blockade of the Ukrainian coastline. The airbase had been used by Russia to launch attacks on targets deep inside Ukraine.
Mr Zelensky did not refer to the blasts in his speech late on Tuesday, but spoke at length about the peninsula, saying: “We will not forget that the Russian war against Ukraine began with the occupation of Crimea.
“This Russian war…began with Crimea and must end with Crimea – with its liberation,” he said.
Mr Zelensky’s latest remarks suggest he believes that Ukraine must retake the peninsula before the war can end – but in the past he has said different things on the issue.
He previously indicated Ukraine could accept peace if Russia returned to their positions before 24 February, meaning retaking Crimea could be a subject of further negotiations.
Russia annexed Crimea in March 2014, after the territory voted to join Russia in a referendum that Ukraine and the West deem illegal.
The vote was hastily organised after unmarked Russian troops took control of several strategic sites around the peninsula.
Earlier that year, months of pro-European protests culminated in the ousting of Ukraine’s Russian-backed president.
On 24 February this year, Moscow launched a full-scale invasion of Ukraine, using Crimea as a springboard to move Russian troops deeper inside Ukraine.