Russian President Vladimir Putin speaks during a meeting with former Russian regional leaders at the Novo-Ogaryovo residence outside Moscow on Nov. 2. (Mikhail Klimentyev/AP)

President Trump and Russian President Vladimir Putin may meet next week at an economic summit in Vietnam, but there is scant optimism in Russia that face-to-face talks will yield any breakthroughs on the long list of issues that divide Washington and Moscow.

Sanctions against Russia, tensions in Syria, the threat of ­military conflict in North Korea and the stalemate over Ukraine top the litany of seemingly in­trac­table differences in the U.S.- Russia relationship.

Looming above it all is the sense in Moscow that the closer special counsel Robert S. Mueller III comes to Trump's inner circle in his investigation into alleged Russian meddling in the 2016 presidential election, the less likely the U.S. president will be to try to reverse the downward spiral with Russia.

Trump, who set out Friday for a 12-day trip to Asia that will take him to Japan, South Korea, China and the Philippines, told Fox News on Thursday that it was possible he could meet with the Russian leader for the second time. Trump is scheduled to appear at the Asia-Pacific Economic Cooperation summit in Danang, Vietnam, which Putin is also scheduled to attend.

"We may have a meeting with Putin," he said. "And again, Putin is very important because they can help us with North Korea. They can help us with Syria. We have to talk about Ukraine."

Putin's spokesman, Dmitry Peskov, said that "we aren't ruling out a Putin-Trump meeting in Vietnam" and that the details "are being coordinated now."

"The importance for international affairs of any contact between the Russian and U.S. presidents can hardly be overestimated," Peskov told reporters on his daily conference call.

The Kremlin offered condolences Wednesday after the terrorist attack Monday in New York City, which killed eight people and wounded a dozen others, the most lethal in the city since 2001.

[Kremlin: Attempts to tie U.S. investigations to Russia ‘baseless’ and ‘ludicrous’]

But Moscow and Washington have been at odds on nearly everything else since Putin and Trump held their first meeting at a summit of the Group of 20 world powers in Hamburg in July.

Trump reluctantly signed tough new sanctions against Russia in August over its annexation of Crimea, its proxy war in eastern Ukraine and its alleged election meddling. The Kremlin, which insists it is not helping separatists fight the government in Kiev and says allegations that it meddled in U.S. political affairs are "groundless," later ordered the U.S. diplomatic mission to Russia to reduce its staff by more than half.

In a speech to foreign policy experts last month, Putin decried an "unprecedented" anti-Russia campaign in the United States and the closure of Russian diplomatic facilities, and promised a symmetrical response to pressure on Russian media by U.S. authorities. He said the United States had flouted nuclear and chemical weapons treaties that Moscow had diligently observed and was threatening a new arms race, to which Moscow's response "will be instant, and I want to warn, symmetrical."

When the State Department published a list of 39 Russian companies and government organizations tied to the defense and intelligence sectors, and warned that anyone in the United States or elsewhere doing significant business with them could be hit with sanctions starting early next year, Peskov called it a sign of "hostility against our country."

[Trump administration reveals new list of potential Russia sanctions]

"There is nothing constructive in Russian-U.S. relations to speak of," Maria Zakharova, a spokeswoman for Russia's Foreign Ministry, said at a briefing Thursday.

In Washington, Mueller's office unveiled charges against former Trump campaign manager Paul Manafort and his associate Richard Gates. The office also revealed the plea agreement of George Papadopoulos, a campaign foreign policy adviser, which described his extensive efforts to broker connections with Russian officials. The document also detailed his contacts with a London-based professor who promised him "dirt" on Hillary Clinton compiled by the Russians, including thousands of emails. Peskov said that linking these charges to Russia was "ludicrous."

Veteran foreign policy analyst Dmitri Trenin, observing the rhetoric in Moscow and the investigative hearings and indictments in Washington, tweeted that it all "suggests that US-

Russian relations will get worse before they get even worse."

Some in Moscow are making the case that the relationship is bound for a long chill.

Alexander Gabuev, a senior fellow at the Carnegie Moscow Center, said that the Cold War-era foreign policy elites in both countries are being replaced by a new generation of leaders who sincerely perceive Russia and the United States as enemies.

In the U.S., Gabuev wrote in a recent report, Russia will be viewed "as a brazen and aggressive global actor . . . which must be put in its place and punished in every conceivable way, through new sanctions, the supply of weapons to counter Russia in post-Soviet conflict zones, and cyber activity."

In Russia, the up-and-coming leaders view "the fight against America as part of their job — even as their national mission," Gabuev wrote. "Just like their American counterparts, many of them believe that the enemy (the United States) is in a state of long-term decay, which is the real reason it is constantly trying to hurt Russia."

[Here is who is under investigation, and why]

Against such a backdrop, Trump and Putin will be challenged to make headway in Vietnam, said Vladi­mir Frolov, a Moscow-based foreign policy analyst.

"Trump wants something from Putin on North Korea, but it is unclear to me if Putin is in a position to grant his wish," Frolov said. "If not, Trump will lose interest in the relationship and it will all go downhill from there."

"Basically, this meeting is the last pit stop before everything goes off the rails completely," he said.

Read more:

Who’s who in the George Papadopoulos court documents

Putin says he thinks Trump ‘agreed’ with assurances that Russia did not interfere in U.S. elections

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