Trump and Putin’s avowed personal rapport masks deeper tensions

But that can-do image is at odds with the two leaders’ records and the new geopolitical reality. Trump and Putin failed to cut deals on everything from arms control to Ukraine during his first term, and the gulf between the two countries has only widened since he left office.

The Russian leader has had warm words for Trump since his election, calling him “courageous" at a public forum last week. But the Kremlin denied that the two men had spoken since the election, despite a Washington Post report that they held a phone call last week.

Not since the demise of the Soviet Union have the stakes been higher. Russia and the U.S. are locked in an escalating conflict in Ukraine, and Moscow stands accused of sabotage operations across Europe, including covert plans to start fires on cargo or passenger planes headed to the U.S. More broadly, Putin is trying to shift the global balance of power by strengthening a coalition of American rivals, including China, Iran and North Korea.

Both Putin and Trump are seeking to establish positions of strength ahead of what are expected to be tough talks on Ukraine, but any window of hope will largely hinge on whether Trump will be able to translate kind words into concrete diplomatic breakthroughs.

When Trump won the 2016 election, Russian lawmakers popped Champagne on the floor of parliament anticipating a new era of U.S.-Russian relations under the businessman who had spent months on the campaign trail praising Putin.

Then the Kremlin didn’t retaliate when Barack Obama, before handing over to Trump, kicked out 35 Russian diplomats alleged to have meddled in the election. Russia hoped instead to turn the page with the incoming president.

But under Trump’s first term, the mood between Washington and Moscow only darkened. Putin and Trump failed to agree on core issues such as arms control, security cooperation and continued U.S. support for Ukraine, which Russian troops invaded in 2014. Russia sought agreements on tactical and intercontinental-range nuclear weapons and a deal that would somehow accommodate Moscow’s demands that Ukraine remain neutral and outside of the North Atlantic Treaty Organization.

Trump’s dealmaking efforts with Putin were in part crimped by allegations that he was secretly beholden to the Kremlin for its hacking campaign against Hillary Clinton, his opponent in the 2016 presidential race. Suspicions that Trump harbored a pro-Russia bias were magnified by later-discredited allegations that his campaign colluded with Kremlin hackers.

Kurt Volker, former NATO ambassador under Trump, said that the president-elect’s warm words toward Putin masked a more mercantile negotiating tactic with world leaders. Trump avoids demonizing the person he is talking to “because he wants to make a deal," Volker said.

“So if you look at his first term, he had a very warm commentary towards Putin," Volker said. “At the same time, he lifted an arms embargo on Ukraine, and kicked the Russians out of San Francisco and called it a spying operation. He threw out about 80 intelligence officers from New York and Washington."

Now Trump and Putin have returned to the warm public rhetoric. Moscow congratulated Trump on his victory and on the campaign trail Trump repeatedly called the Kremlin leader tough and smart. The sentiments reflect Trump’s popularity among some in Russia, where average Russians balanced out their disdain for the U.S. with glee over his election victory on social media. But the camaraderie belies deeper tensions.

For months, Russian troops have been grinding forward on a broad front deeper into Ukraine, taking territory that Moscow intends to keep in any peace agreement. U.S. officials say that Moscow believes it is winning the war, making any talks an impossibility.

“Putin is not ready for any substantive talk around any possible peace plan, because he is not ready to make any concessions. Full stop," said Andrei Kolesnikov, a veteran Russia watcher. “He believes that he has enough financial and emotional resources to continue."

Still, Putin has reasons to fear Trump’s broader policy goals, which could strain Russia’s war effort in new ways.

Trump’s selection of Rep. Mike Waltz, a Green Beret veteran, to be his White House national security adviser could be a double-edged sword for Putin. On the one hand, the lawmaker has criticized the size of U.S. aid to Ukraine and has called on Europe to do more. But he has also warned that Washington could lift restrictions on long-range weapons the U.S. provides to Ukraine, potentially allowing Kyiv to strike deeper into Russian territory, if Putin doesn’t come to the negotiating table.

Meanwhile, Trump has promised to stimulate oil drilling in the U.S., which would contribute to a glut in global oil supplies, a vital revenue stream for the Russian economy that has already been hit by massive Western sanctions. The Kremlin’s wartime economy is showing signs of overheating because of labor shortages.

Trump also wants to step up pressure on North Korea, which has emerged as Moscow’s strategic ally during its war in Ukraine by supplying millions of artillery shells and, more recently, troops near the battlefront in western Russia.

The president-elect has also threatened to hold Iran, another Kremlin ally that has supplied it with drones, directly responsible for Iranian proxies causing chaos in the Middle East. Trump will strengthen ties with Israel, which said it denuded Iran’s air defenses and damaged its missile-production facilities in a recent strike.

But Moscow retains the upper hand for now as its forces move deeper into Ukraine.

Trump’s former national security advisers have warned that Putin could try to flatter the president-elect into a better deal for Moscow, at the expense of Kyiv.

The praise the two leaders have heaped on each other has at times aroused suspicion among political opponents that there is more to the relationship than what is publicly known. A recent book by Bob Woodward reported that the two have exchanged as many as seven phone calls since Trump left office in 2021. Kremlin spokesman Dmitry Peskov has denied that the two had been in contact. Trump neither confirmed nor denied he had held those conversations but said it would be “a smart thing" if he had.

The two leaders have always shown an interest in the other’s company. They first met in 2017, months after Trump came to office, on the sidelines of a Group of 20 summit in Germany. The leaders had planned on a brief meeting but ended up talking for more than two hours and then spoke again during dinner the same day.

Other meetings followed, including a summit in Helsinki where Trump sparked outrage in the U.S. by saying he believed Putin’s assurances that Moscow didn’t meddle in the 2016 elections, contrary to U.S. intelligence assessments.

Likewise, Elon Musk, who was one of Trump’s biggest financial supporters in his recent campaign, has also had regular conversations with Putin and Kremlin officials, The Wall Street Journal reported. Trump has named Musk to lead a new government-efficiency body, though the extent of his influence in the incoming Trump administration is unclear. In a phone call between Trump and Ukrainian President Volodymyr Zelensky last week, Musk made an unplanned appearance on the call.

Although Trump has promised to end the war in Ukraine before he is sworn in as president in January, Putin has already outlined the basis on which he would be willing to come to the negotiating table. There are, in fact, few easy enticements that Trump can offer to make him budge.

Putin wants vast territorial concessions from Ukraine and assurances that Kyiv won’t join NATO, but beyond that he also wants relief from sweeping U.S. sanctions. The president doesn’t have the authority to lift most of those sanctions. That must be legislated through Congress, and Republicans will likely control both houses following the elections.

“Putin might not be opposed to more diplomatic contact, but that doesn’t necessarily lead to him moderating his behavior," said one former U.S. diplomat to Russia. “He believes that he’s doing quite well on the battlefield."

Write to Alan Cullison at alan.cullison@wsj.com and Thomas Grove at thomas.grove@wsj.com