On Tuesday, Polish President Andrzej Duda delivered an emphatic speech in support of Ukraine on the floor of the United Nations General Assembly.

“This brutal war must end, and not be converted into a frozen war,” Duda declared from the rostrum. “This can only be done by restoring the full territorial integrity of Ukraine within its internationally recognized borders!”

“If someone attacks your household, you have the right to defend it, and the neighbors should not stay indifferent,” he continued. “Ukraine would not be able to resist the aggression and effectively stand for its independence if it were not for the assistance of other countries.”

That tone, characteristic of Poland’s approach to the war to date, changed quickly after Ukrainian President Volodymyr Zelensky accused Poland, Hungary, and Slovakia of helping Russia by banning imports of Ukrainian grain in response to complaints by local farmers over unfair competition.

The comments led Poland to summon Ukraine’s ambassador to Warsaw for a diplomatic dressing down, followed by a public version from the Polish president himself.

“Ukraine is behaving like a drowning person clinging to anything available,” Duda told reporters later on Tuesday.”A drowning person is extremely dangerous, capable of pulling you down to the depths.”

Poland appeared to up the ante further on Wednesday when Polish Prime Minister Mateusz Morawiecki said, in response to a question about whether the grain dispute would affect Poland’s support for Ukraine, that Warsaw is “no longer transferring weapons to Ukraine, because we are now arming Poland with more modern weapons.”

It remains unclear whether the apparent policy shift is related to the dispute, but the timing of the comments has drawn significant concern from the West.

To some degree, the contours of this spat should come as no surprise. While European countries have shown a remarkable willingness to accept economic pain to support Ukraine, observers have long worried that this steadfastness would fade as the war drags on.

“[A]lways look at history, geography and interests as both sides see them,” wrote Gerard Araud, a former French UN ambassador, on X. “International relations are anything but romantic. Poland and Ukraine are only united by the existence of a common enemy.”

In this case, Polish leadership is more concerned with impressing voters ahead of elections next month when Duda’s Law and Justice party hopes to stave off a challenge from the Civic Coalition, an increasingly popular center-right bloc. The Law and Justice party reportedly hopes to bolster support among farmers by responding decisively to their concerns about Ukrainian grain.

Though the agriculture ministers from Poland and Ukraine have said they will “work out an option to cooperate on export issues in the near future,” it appears likely that grain issues will continue to create friction between the two countries.

Meanwhile, a larger challenge to Western unity is brewing in Slovakia, where leftist former Prime Minister Robert Fico looks poised to return to power in elections later this month. Fico has said that, if he wins, he would block arms shipments to Ukraine and prevent Kyiv from joining NATO.

“It’s naive to think that Russia would leave Crimea,” Fico recently told the Associated Press. “It’s naive to think that Russia would ever abandon the territory it controls.”

His position is, to a large extent, a reflection of Slovakia’s ambivalence toward the causes of the conflict. While most Western countries firmly blame Russia for the war, fully 51 percent of Slovaks say Ukraine or the West are responsible.

With Slovakian elections set for September 30, the West will soon face far greater challenges in maintaining unity on Ukraine than at any time since the war began.

In other diplomatic news related to the war in Ukraine:

— U.S. President Joe Biden called on world leaders to maintain pressure on Russia to end its war in Ukraine during a speech at the UN, according to the New York Times. “Russia believes that the world will grow weary and allow it to brutalize Ukraine without consequence,” Biden said. “We have to stand up to this naked aggression today to deter other would-be aggressors tomorrow.” In contrast, a number of Global South leaders, including Brazilian President Luiz Inacio “Lula” da Silva and Colombian President Gustavo Petro, used their General Assembly speeches to call for talks to end the war in Ukraine.

— Ukrainian President Volodymyr Zelensky met with Biden and a range of other top American officials during a trip to the United States for the UN General Assembly, according to AP News. But, as Blaise Malley recently wrote in RS, the visit was a far cry from the warm welcome Zelensky received in his previous U.S. trip. “Zelensky returns to a vastly changed landscape in Washington Thursday, as a growing number of GOP lawmakers have expressed their reluctance — or outright opposition — to continued funding for Ukraine,” Malley reported.

— Mark Milley, Washington’s top military official, toldCNN that, while he remains hopeful about Ukraine’s counteroffensive, the larger goal of expelling all Russian troops from the country is “a very high bar.” “It's going to take a long time to do it,” Milley argued. The comments come as the mood around the chances of Ukrainian military success continues to sour, with even mainstream outlets like the New York Times giving dour takes on the future of the war. “The currency of the counteroffensive is ammunition, vehicles and human lives,” Times reporters Thomas Gibbons-Neff and Lauren Leatherby wrote on Wednesday. “This is what is certain: More people will die, more buildings will burn and the surrounding farmlands will be seeded with land mines [sic] and unexploded shells that probably will take decades to clear.”

U.S. State Department news:

The State Department did not hold a press briefing this week.