KYIV, Ukraine (AP) — Russian missiles and artillery pounded cities across Ukraine early Thursday, sparking fires, killing at least two people and trapping others under rubble, authorities said, as Poland said it would stop providing weapons to its ally amid a trade dispute.

The early morning wave of missile strikes on what’s known as the International Day of Peace was Russia’s largest in over a month, and came as world leaders meet at United Nations General Assembly in New York. In a speech there, Ukrainian President Volodymyr Zelenskyy denounced Russia as “a terrorist state.”

Zelenskyy was to meet Thursday with President Joe Biden and congressional leaders in Washington with an additional $24 billion aid package hanging in the balance.

Poland, which has been a major supporter of Ukraine, said it would stop transferring its weapons to its neighbor as it works to modernize its own military, but denied the decision was linked to a simmering dispute over a temporary ban on Ukrainian grain imports.

Polish Prime Minister Mateusz Morawiecki said the decision would not affect NATO and U.S. weapons transfers through Poland.

“We are no longer transferring any weapons to Ukraine because now we will arm ourselves with the most modern weapons,” he said in an interview on the private TV broadcaster Polsat News late Wednesday.

A dispute about whether Ukrainian grain should be allowed to enter the domestic markets of Poland and other European Union countries has pushed the tight relationship between Kyiv and Warsaw to its lowest point since Russia invaded Ukraine last year.

Morawiecki stressed that Poland would defend its economic interests, but added that the dispute over grain imports would not hurt Ukraine’s security.

“We are not going to risk the security of Ukraine,” he said. Poland has transferred large amounts of its older weapons to Ukraine and has been upgrading its own inventory with new equipment purchased from South Korea and other countries.

Air raid sirens sounded repeatedly across Ukraine, as Russia launched dozens of missiles and, near the front lines, likely used shorter-range artillery to pound the southern city of Kherson. Two people were killed in Kherson Thursday and at least five injured after a residential building was hit, said regional Governor Oleksand Prokudin.

Seven people were injured in Kyiv, including a 9-year-old girl, Mayor Vitalii Klitschko said, as missile strikes blew out windows in buildings and cars and left fires burning around crumpled metal wreckage.