KYIV: Ukraine ruled out a ceasefire orany territorial concessions to Russia, and Poland’s presidentsaid any loss of Ukrainian territory would be a “huge blow” tothe entire West as he warned against appeasing Russian President Vladimir Putin.

Air raid sirens blared across Ukraine on Monday morning,sounding the daily alarm ahead of anticipated attacks by Russianforces in the east and south of the country.

Russia has stepped up its pounding of the Donbas andMykolaiv regions with air strikes and artillery fire, in whatUkraine has described as a “scorched-earth” strategy to wincontrol of the eastern front.

“The war must end with the complete restoration of Ukraine’sterritorial integrity and sovereignty,” Andriy Yermak, Ukraine’spresidential chief of staff, said in a Twitter post on Sunday.

Polish President Andrzej Duda offered Warsaw’s backing,telling lawmakers in Kyiv on Sunday that the internationalcommunity had to demand Russia’s complete withdrawal and thatsacrificing any territory would be a “huge blow” to the entireWest.

“Worrying voices have appeared, saying that Ukraine shouldgive in to Putin’s demands,” Duda said, the first foreign leaderto address the Ukrainian parliament in person since Russia’sFeb. 24 invasion.

“Only Ukraine has the right to decide about its future.”

Ukraine and Poland agreed to establish a joint bordercustoms control and work on a shared railway company to ease themovement of people and increase Ukraine’s exports.

Most Ukrainian refugees have crossed to the European Unionthrough border points in Poland, Slovakia, Hungary and Romania.Poland has granted the right to live and work and claim socialsecurity payments to over 3 million Ukrainians.

Ukraine, one of the world’s major exporters of wheat andcorn, has been unable to export nearly 25 million tonnes ofgrains, causing global food prices to soar.

STRONGER SANCTIONS PLEA

Speaking to the same parliamentary session, UkrainianPresident Volodymyr Zelenskiy renewed a plea for strongereconomic sanctions against Moscow.

“Half-measures should not be used when aggression should bestopped,” he said.

Zelenskiy said at a news conference with Duda that 50 to 100Ukrainians are dying every day on the war’s eastern front inwhat appeared to be a reference to military casualties.

Russia is waging a major offensive in Luhansk, one of twoprovinces in Donbas, after ending weeks of resistance by thelast Ukrainian fighters in the strategic southeastern port ofMariupol.

The heaviest fighting focused around the twin cities ofSievierodonetsk and Lysychansk, interior ministry adviser VadymDenysenko told Ukrainian television on Sunday.

The cities form the eastern part of a Ukrainian-held pocketthat Russia has been trying to overrun since mid-April, when itshifted focus to the south and east after abandoning an attemptto take Kyiv.

Serhiy Gaidai, the governor of Luhansk, said in a localtelevision interview that Russia was using “scorched-earth”tactics.

“They are wiping Sievierodonetsk from the face of theearth,” he said.

Russian shelling and “heavy fighting” near Sievierodonetskhas continued, but the invading forces failed to secure thenearby village Oleksandrivka, a Ukrainian military statementsaid.

Russia’s defence ministry said on Sunday its forcespummelled Ukrainian command centres, troops and ammunitiondepots in Donbas and the Mykolaiv region in the south with airstrikes and artillery.

Reuters was unable to independently verify those battlefieldreports.

Russian-backed separatists already controlled parts ofLuhansk and neighbouring Donetsk before the invasion, but Moscowwants to seize the remaining Ukrainian-held territory in theregion.

Ukraine’s military said seven civilians were killed andeight injured during Russian attacks in Donbas on Sunday.Numbers for Luhansk were not disclosed.

NO CONCESSIONS, NO CEASEFIRE

Ukraine’s lead negotiator, Zelenskiy adviser MykhailoPodolyak, ruled out any territorial concessions and rejectedcalls for an immediate ceasefire in an interview with Reuters onSaturday, saying any concessions would backfire because Russiawould use the break in fighting to come back stronger.

Recent calls for an immediate ceasefire have come from U.S.Defences Secretary Lloyd Austin and Italian Prime Minister MarioDraghi.

The end of fighting in Mariupol, the biggest city Russia hascaptured, gave Putin a rare victory after a series of setbacksin nearly three months of combat.

Full control of Mariupol gives Russia command of a landroute linking the Crimean Peninsula, which Moscow seized in2014, with mainland Russia and parts of eastern Ukraine held bypro-Russia separatists.

Russian soldiers entered Mariupol’s Azovstal steel-works onSunday, the last Ukrainian stronghold, and began clearing minesand debris from the destroyed complex.

Along with sanctions, Western nations have stepped upweapons supplies and other aid to Ukraine, including a new $40billion package from the United States.

Moscow says Western sanctions and aid for Kyiv amount to a“proxy war” by Washington and its allies.

Putin calls the invasion a “special military operation” todisarm Ukraine and rid it of radical anti-Russian nationalists.Ukraine and its allies have dismissed that as a baseless pretextfor the war, which has killed thousands of people in Ukraine anddisplaced millions.