Moscow believes its leader, ex-spy master Vladimir Putin, can extract major concessions from President Donald Trump when the two meet for the first time next week, European officials tell The Daily Beast.

The officials say their intelligence indicates Putin thinks he can outmaneuver Trump at the G-20 summit, playing on promises of cooperation on areas like counterterrorism to win concessions like a reduction in the raft of sanctions against Russia.

“When you meet Russia, don’t give anything away for free,” one Western official warned, echoing the fears of many European diplomats ahead of next week’s Trump-Putin meeting on the fringes of the G-20 in Germany.

Their misgivings highlight concern that Trump’s inexperience and Putin’s ability to flatter will slowly degrade the U.S. alliance with Europe over time, and boost Moscow back to near-superpower status while extracting no changes to its aggressive, expansionist behavior.

Trump’s administration has been dogged by investigations into Moscow’s calculated campaign to influence the 2016 presidential elections in Trump’s favor. Before he became president, Trump fawned over the “real leader” in the Kremlin who he hoped would become his “best friend,” and he couldn’t quite make up his mind whether he had ever met Putin.

In the White House, Trump has been reluctant to publicly blame Russia for the election hacking, while showing no such reticence in publicly rebuking NATO allies for not investing enough in their own defense.

“If Russia hacked, if Russia did anything having to do with our election, I want to know about it,” he told NBC on May 11, despite his own Director of National Intelligence Dan Coats telling lawmakers on the same day that “only Russia’s senior-most officials could have authorized the 2016 U.S. election-focused data thefts and disclosures, based on the scope and sensitivity of the targets.”

That’s partly why some European officials remain wary of any rapprochement between Trump and Putin, despite pledges by Pentagon chief Jim Mattis this week to increase resources to protect NATO members—and despite the Trump State Department re-upping sanctions against Moscow over its annexation of Crimea and continued military interference in Ukraine.

“There’s definitely some anxiety overseas. They are worried about a deal that may be struck in the meeting on the fly,” said Brookings Institution’s Thomas Wright of his conversations with European officials. “Putin is very good at these first meetings. He has an agenda and knows how to maneuver people. If Trump isn’t prepared, the longer he stays in the room, the more dangerous it is.”

Putin infamously charmed previous Presidents George W. Bush and Barack Obama, who responded with moves to increase cooperation, only to be disappointed by Russia’s invasion of Georgia under Bush, and Crimea and Ukraine in the Obama years.

National Security Adviser Lt. Gen. H.R. McMaster told reporters Thursday that no agenda had been set for the meeting, but he indicated that Trump would be carrying both carrot and stick.

“Our relationship with Russia is not different from that with any other country in terms of us communicating to them really what our concerns are, where we see problems with the relationship but also opportunities,” McMaster said in answer to a question from The Daily Beast.

McMaster said Trump had already ordered his staff to find ways “to confront Russia’s destabilizing behavior” and deter it, whether it’s cyberthreats or “political subversion” here or in Europe.

“Nobody wants a major power war, right?” he asked rhetorically.

Mattis spoke far more bluntly in Europe Wednesday, slamming Putin’s military adventurism at the cost of his people’s prosperity.

“Russia must know both what we stand for and equally, what we will not tolerate,” he said in remarks to European military officials in Germany. “Their leader making mischief beyond Russian borders will not restore their fortunes or rekindle their hope.”

Those stern messages from McMaster and Mattis are the ones European officials hope Trump will take into the meeting with Putin.

“I hear a consistent message from many levels they want to have a cooperative relationship with Russia, and work collectively on shared national security interests, but Russia has to earn that relationship by putting its money where its mouth is,” the a Western official told The Daily Beast.

The foreign officials spoke on condition of anonymity to discuss the intelligence and the discussions ahead of Trump’s international trip. The Russian embassy in Washington declined requests for comment.

The Western official said a warming of U.S.-Russian relations wouldn’t be a bad thing, because so many key international issues rely on the two major powers talking.

“We need that relationship to work,” the official said. “It’s crucial to what we are trying to achieve in North Korea, Iran, and Syria,” the official added, namely pressuring North Korean dictator Kim Jong Un to ditch nuclear weapons, pressuring Iran to stay nuclear weapons-free and convincing Syrian dictator Bashar al-Assad to step down.

Yet the Trump White House has sent mixed signals, exploring the unilateral reduction of sanctions on Russia earlier this year. A senior administration official said the National Security Council was simply asking the State Department if the sanctions against Russia were hurting U.S. businesses more than they were hurting Moscow, but the State Department officials who’d crafted the original sanctions were skeptical.

The Guardian reported Thursday that Trump had asked White House officials to draw up a list of diplomatic sweeteners he could offer Putin at the meeting, but a senior administration official insisted no such request was made. The official insisted on anonymity as a condition of denying the allegations.

But Trump has remained diffident in his public comments about Moscow, even after administration officials concluded Russia was likely aware in May that Syrian regime forces were about to fire sarin-laden bombs on civilians in May, because Russian military advisers were stationed at the base that launched the attack.

To understand Putin, Trump need look no further than an unclassified Defense Intelligence Agency report released this week, that says Moscow sees the U.S. as one of its fiercest enemies.

“The Kremlin is convinced the United States is laying the groundwork for regime change in Russia,” the report said, adding that Moscow blames American meddling for a laundry list of woes including the Arab Spring and the overthrow of pro-Putin leaders in Ukraine, as well as the revolutions in Georgia, Ukraine, and Kyrgyzstan.

“He should be ready for Russian expectations that it is a global power [that] deserves to be treated like an equal in spite of flagrantly violating international norms,” said Mara Karlin, a former senior defense official under the Obama and Bush administrations who now teaches at Johns Hopkins-SAIS.

“He should be ready for complaints about the European Reassurance Initiative [money to European bolster security], missile defense in Europe, and the U.S. military’s increased focus on European security more broadly,” she said in an email, harkening back to previous negotiations with Russian officials.

The Trump administration just stepped up its commitment to the European Reassurance Initiative to $4.8 billion next year, though it was started by the Obama administration to bolster the defense of NATO allies after Russia’s military action in Crimea and Ukraine. It includes keeping American troops stationed in countries along Russia’s border, a sore subject for Putin.

“Both are masters in the dark arts of deception, misdirection, and nationalist symbolism,” said former Obama defense official Derek Chollet of the two leaders. “The obvious card Putin plays is to offer something on ISIS and Syria. But what does he demand in return? Lifting sanctions? Pulling troops out of the Baltics? And does Trump take the bait?” he asked in an email to The Daily Beast.

And will Trump shame Putin publicly over U.S. election interference, as he just shamed tiny Gulf ally Qatar over alleged terrorist funding, Chollet asked. “Or does he agree with Putin that it is a hoax?”