The Ukrainian opposition leader, Petro O. Poroshenko, has appealed for political unity as turmoil intensifies in his country after he was blocked from leaving for a trip abroad that he said was aimed at lobbying for more military support.
“It was a surprise and shock for me when they tried to stop me,” Mr. Poroshenko said in an interview on Monday, three days after he was prevented from leaving Ukraine on a scheduled trip to Poland, and then to the United States for what he said were meetings at Congress and the Pentagon.
But he urged in a video call for politicians to stick together and cease personal attacks that created divisions at a critical time for Ukraine. “The first loser is Ukraine,” he said, “because we give additional fuel to the skeptics of Ukraine.”
Ukraine’s intelligence agency, the S.B.U., said on Saturday that it had blocked the departure of Mr. Poroshenko, a former president who leads the opposition in the Ukrainian Parliament, to prevent his trip from being used for propaganda purposes by Russia. The S.B.U. said that Mr. Poroshenko had planned to meet with Prime Minister Viktor Orban of Hungary, who, the secret service said, has close ties with Russia.
Mr. Poroshenko denied that he had planned to meet with Mr. Orban. He said he had written him a letter last month but had not arranged a meeting. Mr. Orban is the main obstacle to a package of European aid being considered for Ukraine.
Mr. Poroshenko said his planned meetings in Poland and the United States were important for the country ahead of critical decisions on support for Ukraine coming up in the United States. “This is one of the most important 10 days in Ukrainian history,” he said.
President Volodymyr Zelensky was scheduled to make a direct appeal to U.S. senators on Tuesday aimed at reminding them what is at stake if they fail to quickly approve emergency military aid for his nation, but pulled out of the session unexpectedly. That warning came a day after White House officials said that the United States would soon run out of money to send weapons to Ukraine.
The Democratic-led Senate will vote on Wednesday about whether to approve more than $61 billion in Ukraine-focused assistance as part of a $106 billion national security package, which comes as Republican support for funding Ukraine’s war effort is waning and an emergency funding package is stalled in Congress.
The political turmoil in Ukraine comes as the country enters its second winter of full-scale war with Russia and as the public braces for more attacks on cities and infrastructure, while its troops face grinding fighting on three fronts.
A summer counteroffensive failed to produce a hoped-for breakthrough against Russian defenses on the southeastern front, and while Ukrainian troops have gained some success in the south and against Russian naval forces in the Black Sea, they are suffering sustained attacks in the east.
As the military campaign has run into difficulties, criticism has started to rise within Ukraine’s political leadership. The commander of Ukrainian forces, Gen. Valery Zaluzhny, wrote in a paper recently that the war was in a stalemate and would stay that way unless Ukraine received increased and more technologically sophisticated military equipment. Mr. Zelensky swiftly chastised the general and denied that the war was in a stalemate.
Since then, rumors have abounded that General Zaluzhny will be replaced. A member of Parliament in Mr. Zelensky’s party, Mariana Bezuhla, who is a deputy chair of the Committee on National Security, Defense and Intelligence in Parliament, has criticized General Zaluzhny repeatedly on Facebook for failures in planning, even running a poll asking people to vote on his replacement.
The attacks on General Zaluzhny, who is enormously popular within the armed forces, have led others to criticize the government and Mr. Zelensky’s administration, with complaints that the president interferes with military decisions and fires commanders without consulting with his military chief.
Vitali Klitschko, the popular mayor of Kyiv and a former boxing champion, expressed support for General Zaluzhny in an interview this weekend, saying the general was right to tell the truth about the situation. And the mayor took a side swipe at Mr. Zelensky, saying his slide in opinion polls was because of mistakes he made in failing to prepare for the war.
Both Mr. Klitschko and Mr. Poroshenko are political rivals of Mr. Zelensky but had largely buried their differences since the Russian invasion in February last year. But rivalries have emerged from time to time, such as when Mr. Zelensky criticized the mayor for not preparing air raid bunkers in the city sufficiently.
Mr. Poroshenko said he went to the president in the first days of the war to offer his hand. “I told him, ‘I am not the leader of the opposition, and you are not my opponent anymore.’ Russian tanks were kilometers from my office,” he said.
Personal rivalry was most likely behind Mr. Poroshenko’s travel ban, one analyst said, but in the end Mr. Poroshenko and Mr. Zelensky agreed on the need to fight Russia and build alliances with the West. “Their cooperation is inevitable,” said the analyst, Petro Burkovskiy, the executive director of a nonprofit, nonpartisan think tank called the Democratic Initiatives Foundation.
The politicking was a sign of a functioning democracy, insisted Oleksiy Haran, professor of comparative politics at the National University of Kyiv-Mohyla Academy. “Ukraine remains a democracy even under martial law,” he said. “There are opposition channels. There is a lot of debate, it is very important to keep that in mind.”
He said the blocking of Mr. Poroshenko’s travel was a “mistake by the authorities.”
Yehor Cherniev, a member of Parliament from Mr. Zelensky’s party, said Mr. Poroshenko would have another opportunity to travel.
And although Mr. Cherniev, a deputy chairman of the Committee on National Security, Defense and Intelligence, agreed that an end of Western assistance would spell disaster for Ukraine, he was dismissive that Mr. Poroshenko could influence the state of affairs. “He does know a lot of people, but there is no evidence that they listen to him,” he said.
Mr. Poroshenko, who has long supported a pro-West, pro-European trajectory for Ukraine, said he had intended on his trip to lobby for continued commitment to Ukraine in its war against Russia.
Most important, Mr. Poroshenko said, was the decision facing Congress on the financial and military assistance package for Ukraine proposed by the Biden administration. He said he had planned to meet the House speaker, Mike Johnson, and other Republican lawmakers, as well as officials at the Pentagon.
The holdup of vital military assistance represents an existential threat to Ukraine as it faces renewed Russian attacks, he said.
“We have an extreme lack of ammunition on the front line, and I know that directly from the soldiers,” he said. “Now this is a question of the existence of Ukraine.”
He also made a direct appeal to American members of Congress.
“Please do not block the Ukrainian military,” he said. “Do not block Ukrainians’ ability to defend ourselves, because we are defending all the free world, including the U.S.”
Oleksandr Chubko contributed reporting from Mykolaiv, Ukraine.