By NEBI QE­NA and CARA AN­NA-As­so­ci­at­ed Press

KYIV, Ukraine (AP) — Ukrain­ian Pres­i­dent Volodymr Ze­len­skyy called on peo­ple world­wide to gath­er in pub­lic Thurs­day to show sup­port for his em­bat­tled coun­try as U.S. Pres­i­dent Joe Biden and oth­er world lead­ers met for talks fo­cused on pres­sur­ing Rus­sia to end the in­va­sion that is en­ter­ing its sec­ond month.

“Come to your squares, your streets. Make your­selves vis­i­ble and heard,” Ze­len­skyy said in Eng­lish dur­ing an emo­tion­al video ad­dress late Wednes­day that was record­ed in the dark near the pres­i­den­tial of­fices in Kyiv. “Say that peo­ple mat­ter. Free­dom mat­ters. Peace mat­ters. Ukraine mat­ters.”

Brus­sels was the cen­ter Thurs­day of a flur­ry of diplo­mat­ic ac­tiv­i­ty. NA­TO Sec­re­tary-Gen­er­al Jens Stoltenberg opened an emer­gency sum­mit bring­ing to­geth­er Biden and oth­er lead­ers by say­ing that the al­liance is de­ter­mined to con­tin­ue to ratch­et up the costs on Rus­sia for its ag­gres­sion.

Rus­sia un­leashed its in­va­sion Feb. 24 in Eu­rope’s biggest of­fen­sive since World War II, but in­stead of swift­ly top­pling Ukraine’s gov­ern­ment, its forces are bogged down in a grind­ing mil­i­tary cam­paign and its econ­o­my is la­bor­ing un­der pun­ish­ing in­ter­na­tion­al sanc­tions.

“This is a month now,” Ze­len­skyy said Thurs­day in an ad­dress to Swe­den’s par­lia­ment, the lat­est of many to whom the Ukrain­ian leader has plead­ed for help. “We have not seen a de­struc­tion of this scale since World War II.”

Af­ter a month of fight­ing, West­ern an­a­lysts say Ukrain­ian forces need stock­ing up again with the weapons that have helped them slow and re­pel Russ­ian ad­vances. Both sides claimed Thurs­day to have in­flict­ed more blows. Ukraine’s navy said it sank a ship that had been used to re­sup­ply the Russ­ian cam­paign with ar­mored ve­hi­cles. Rus­sia claimed to have tak­en a town, Izyum, in east­ern Ukraine af­ter heavy fight­ing.

But in many ar­eas, Ukrain­ian forces ap­pear to have bat­tled Russ­ian troops to a stale­mate, an out­come that seemed un­like­ly when Russ­ian Pres­i­dent Vladimir Putin un­leashed his in­va­sion force.

De­ter­mined to make Putin pay, and un­der in­tense pres­sure from Ze­len­skyy to do more, West­ern na­tions said more help is on the way for Ukraine.

Eu­ro­pean Union na­tions signed off on an­oth­er 500 mil­lion eu­ros ($550 mil­lion) in mil­i­tary aid. And Biden was ex­pect­ed to dis­cuss new sanc­tions on Rus­sia, along with more mil­i­tary aid for Ukraine, with NA­TO mem­bers. He will al­so talk with lead­ers of the G7 in­dus­tri­al­ized na­tions and the Eu­ro­pean Coun­cil in a se­ries of meet­ings on Thurs­day.

Send­ing a sig­nal that sanc­tions have not brought it to its knees, Rus­sia re­opened its stock mar­ket Thurs­day, but al­lowed on­ly lim­it­ed trad­ing. The curbs on a re­duced num­ber of stocks in­clud­ing en­er­gy gi­ants Gazprom and Ros­neft were meant to pre­vent a re­peat of a mas­sive sell­off that took place Feb. 24. For­eign­ers were barred from sell­ing and traders were barred from short sell­ing, or bet­ting prices would fall. The bench­mark MOEX in­dex gained 8% in the first min­utes of trad­ing.

In Ukraine, Russ­ian troops are bom­bard­ing tar­gets from afar, falling back on tac­tics they used in re­duc­ing cities to rub­ble in Syr­ia and Chech­nya.

“Just look at what the Russ­ian army has done to our coun­try,” Ze­len­skyy said in his ad­dress to Swedish law­mak­ers. “A month of bomb­ings sim­i­lar to what we have seen in Syr­ia.”

It is still un­clear ex­act­ly how many troops Rus­sia has lost in pur­su­ing Putin’s aims. Rus­sia hasn’t giv­en an up­date since March 2, when it ac­knowl­edged near­ly 500 sol­diers killed and al­most 1,600 wound­ed. NA­TO es­ti­mates, how­ev­er, that be­tween 7,000 and 15,000 Russ­ian troops have been killed — the lat­ter fig­ure about what Rus­sia lost in a decade of fight­ing in Afghanistan.

Ukraine al­so claims to have killed six Russ­ian gen­er­als. Rus­sia ac­knowl­edges just one.

Ukraine has re­leased lit­tle in­for­ma­tion about its own mil­i­tary loss­es, and the West has not giv­en an es­ti­mate. Ze­len­skyy said near­ly two weeks ago that about 1,300 Ukrain­ian troops had been killed.

Hav­ing failed to take out Ukraine’s gov­ern­ment with a light­ning-quick strike in the first month, a fear go­ing for­ward is of the Krem­lin pos­si­bly re­sort­ing to oth­er more de­struc­tive weapons in its ar­se­nal.

In an omi­nous sign that Moscow might con­sid­er us­ing nu­clear weapons, se­nior Russ­ian of­fi­cial Dmit­ry Ro­gozin said the coun­try’s nu­clear force would help de­ter the West from in­ter­ven­ing in Ukraine.

“The Russ­ian Fed­er­a­tion is ca­pa­ble of phys­i­cal­ly de­stroy­ing any ag­gres­sor or any ag­gres­sor group with­in min­utes at any dis­tance,” said Ro­gozin, who heads the state aero­space cor­po­ra­tion, Roscos­mos, and over­sees mis­sile-build­ing fa­cil­i­ties. He not­ed in his tele­vised re­marks that Moscow’s nu­clear stock­piles in­clude tac­ti­cal nu­clear weapons, de­signed for use on bat­tle­fields, along with far more pow­er­ful nu­clear-tipped in­ter­con­ti­nen­tal bal­lis­tic mis­siles.

U.S. of­fi­cials long have warned that Rus­sia’s mil­i­tary doc­trine en­vis­ages an “es­ca­late to deesca­late” op­tion of us­ing bat­tle­field nu­clear weapons to force the en­e­my to back down in a sit­u­a­tion when Russ­ian forces face im­mi­nent de­feat. Moscow has de­nied hav­ing such plans.

Ro­gozin, known for his blus­ter, did not make clear what ac­tions by the West would be seen as med­dling, but his com­ments al­most cer­tain­ly re­flect think­ing in­side the Krem­lin.

For civil­ians, the mis­ery has been un­re­lent­ing.

In the south, the en­cir­cled port city of Mar­i­upol has seen the worst dev­as­ta­tion of the war, en­dur­ing weeks of bom­bard­ment and, now, street-by-street fight­ing. But Ukrain­ian forces have pre­vent­ed its fall, thwart­ing an ap­par­ent bid by Moscow to ful­ly se­cure a land bridge from Rus­sia to Crimea, seized from Ukraine in 2014.

In their last up­date, over a week ago, Mar­i­upol of­fi­cials said at least 2,300 peo­ple had died, but the true toll is prob­a­bly much high­er. Airstrikes in the past week de­stroyed a the­ater and an art school where civil­ians were shel­ter­ing.

Ze­len­skyy said 100,000 civil­ians re­main in the city, which had a pop­u­la­tion of 430,000 be­fore the war. Ef­forts to get des­per­ate­ly need­ed food and oth­er sup­plies to those trapped have of­ten failed.

In the be­sieged north­ern city of Cherni­hiv, Russ­ian forces bombed and de­stroyed a bridge that was used for aid de­liv­er­ies and civil­ian evac­u­a­tions, re­gion­al gov­er­nor Vi­ach­eslav Chaus said.

Katery­na Mytke­vich, 39, who ar­rived in Poland af­ter flee­ing Cherni­hiv, wiped away tears as she said the city is with­out gas, elec­tric­i­ty or run­ning wa­ter, and en­tire neigh­bor­hoods have been de­stroyed.

“I don’t un­der­stand why we have such a curse,” she said.

An­na re­port­ed from Lviv, Ukraine. As­so­ci­at­ed Press writ­ers Robert Burns in Wash­ing­ton, Yuras Kar­manau in Lviv and oth­er AP jour­nal­ists around the world con­tributed to this re­port.