Ukrainian President Volodymyr Zelensky warned Thursday that any "pauses" in Ukraine's defence against the Russian invasion would only help Moscow to re-arm and allow it to "run us over".
He was speaking from Estonia, as Moscow and Kyiv accused each other of targetting civilians in their missile strikes in a sharp escalation of attacks, and as three Black Sea countries signed an agreement on clearing mines from its waters.
Zelensky was visiting the Estonian capital Tallinn on the second stage of a tour of staunch Baltic allies, part of efforts to bolster support for Kyiv with the war nearing its second anniversary.
"Give the Russian Federation two to three years, then they will simply run us over," he said at a news conference with the Estonian President Alar Karis.
"We wouldn't take that risk... There will be no pauses in favour of Russia."
A "long war" with Russia would not be good for Ukraine," Zelensky insisted.
Karis called for "no limits on providing Ukraine with arms", also suggesting that Ukraine should be allowed to strike inside Russia with Western weapons.
"We must understand that in a war it's inevitable to attack the military objects of the aggressor, to slow the enemy's forces down and weaken them," he said.
Earlier in January, Polish Foreign Minister Radoslaw Sikorski called on Western allies to deliver long-range missiles to Ukraine to help Kyiv target Russian "launch sites and command centres".
In Tallinn, Zelensky restated Ukraine's credentials for NATO membership, arguing that its army would strengthen the bloc's eastern flank.
NATO would gain "an army with military experience -- not theory but practice", he said.
Ukraine has expressed some frustration towards Western allies for the lack of a timeframe to join the Western security alliance.
NATO members Turkey, Bulgaria and Romania meanwhile signed an agreement in Istanbul Thursday on demining the Black Sea to ensure safe waters after Russia's war in Ukraine.
The Russian navy mined Ukraine's Black Sea coastline in the early stages of its invasion nearly two years ago.
In Ukraine meanwhile, local officials said two Russian missiles had hit a hotel in the city of Kharkiv late Wednesday, 13 people including foreign journalists.
"There were no military personnel there," Mayor Igor Terekhov posted on Telegram.
Hours earlier, the authorities in the Russian border city of Belgorod said on Wednesday they had evacuated dozens of children following deadly Ukrainian missiles strikes there.
Zelensky arrived in Tallinn overnight along with Foreign Minister Dmytro Kuleba.
Estonia, one of Ukraine's main allies and a NATO member, has called for continued support for Kyiv as some allies waver.
"Democratic countries have done a lot to assist Ukraine," said Estonia's leader Karis. "But we must collectively do more to ensure Ukraine wins and the aggressor is defeated."
Zelensky appealed for badly needed air-defence systems when he began his tour on Wednesday in Lithuania, warning that Western hesitation on aid for Ukraine was emboldening Russia.
He is expected to travel to Latvia later on Thursday, the third leg of his first foreign trip abroad this year.
