(NewsNation Now) — A former American ambassador to Ukraine says the dust-up between President Joe Biden and Russia’s Vladimir Putin over the buildup of Russian troops on the Ukraine border will likely come to very little.

John Herbst, a diplomat under former President George W. Bush, told NewNation that there’s an approximately 5% chance that Russia would invade its neighboring nation.

Discussing a proposed call between Biden and Putin next week, Herbst said that Putin doesn’t have a leg to stand on with his current posturing.

“We now are talking to Moscow in connection with their latest provocation, this massive buildup on Ukraine’s border, or near Ukraine’s border. And Moscow is now asking to be paid for undoing their own provocations. I don’t see why the United States or NATO would do this.”

Moscow has already sworn not to take any action with Ukraine, Herbst said.

“Moscow had a solemn obligation in the Budapest Memorandum and under various other international agreements not to invade Ukraine, not to seize an ex-Ukrainian territory, and they ignored it,” he said.

Biden on Friday pledged to make it “very, very difficult” for Putin to take military action in Ukraine and said new initiatives coming from his administration are intended to deter Russian aggression.

The president offered the measured warning to Putin in response to growing concern about a Russian buildup of troops on the Ukrainian border and increasingly bellicose rhetoric from the Kremlin.

“What I am doing is putting together what I believe will be the most comprehensive and meaningful set of initiatives to make it very, very difficult for Mr. Putin to go ahead and do what people are worried he may do,” Biden told reporters.

There are signs that the White House and Kremlin are close to arranging a conversation next week between Biden and Putin. Putin’s foreign affairs adviser Yuri Ushakov told reporters Friday that arrangements have been made for a Putin-Biden call in the coming days, adding that the date will be announced after Moscow and Washington finalize details. The Russians say a date has been agreed upon, but declined to say when.

Biden and Ukrainian President Volodymyr Zelenskyy have also tentatively agreed to have a call next week, according to a person close to the Ukrainian president who was not authorized to speak publicly and spoke on condition of anonymity.

White House press secretary Jen Psaki said administration officials have “engaged in the possibility” of a Biden-Putin call. White House officials did not respond to a request for comment on the expected Zelensky call.

“It certainly would be an opportunity to discuss our serious concerns about the bellicose rhetoric, about the military buildup that we’re seeing on the border of Ukraine,” Psaki said of a potential Biden-Putin call.

Biden did not detail what actions he was weighing. But Russian Foreign Minister Sergey Lavrov, who met Thursday with Secretary of State Antony Blinken in Sweden, said the U.S. has threatened new sanctions. He did not detail the potential sanctions but suggested the effort would not be effective.

“If the new ‘sanctions from hell’ come, we will respond,” Lavrov said. “We can’t fail to respond.”

Psaki said the administration would look to coordinate with European allies if it moved forward with sanctions. She noted that bitter memories of Russia’s 2014 annexation of Crimea, the Black Sea peninsula that had been under Ukraine’s control since 1954, are front of mind as the White House considers the way forward.

“We know what President Putin has done in the past,” Psaki said. “We see that he is putting in place the capacity to take action in short order.”

Deep differences were on display during the Blinken-Lavrov meeting, with the Russia official charging the West was “playing with fire” by denying Russia a say in any further NATO expansion into countries of the former Soviet Union. Zelenskyy has pushed for Ukraine to join the alliance, which holds out the promise of membership but hasn’t set a timeline.

Blinken this week said the U.S. has “made it clear to the Kremlin that we will respond resolutely, including with a range of high-impact economic measures that we’ve refrained from using in the past.”

He did not detail which sanctions were being weighed, but one potentially could be to cut off Russia from the SWIFT system of international payments. The European Union’s Parliament approved a nonbinding resolution in April to cut off Russia from SWIFT if its troops entered Ukraine.

Such a move would go far toward blocking Russian businesses from the global financial system. Western allies reportedly considered such a step in 2014 and 2015, during earlier Russian-led escalations of tensions over Ukraine.

Then-Russian Prime Minister Dmitry Medvedev said it would be tantamount to “a declaration of war.”

U.S.-Russia relations have been rocky since Biden took office.

In addition to the Ukraine issue, the Biden administration has levied sanctions against Russian targets and called out Putin on Kremlin interference in U.S. elections, malign cyberactivity against U.S. businesses, and the treatment of opposition figure Alexei Navalny, who was poisoned last year and then later imprisoned.

Putin and Biden met face to face in Geneva in June, with the U.S. president warning if Russia crossed certain red lines — including going after major American infrastructure — his administration would respond and “the consequences of that would be devastating.”

Herbst, though, sees that as unlikely.

“Putin, while he’s a risk-taker, does not take stupid risks,” he explained. “And while he may huff and puff that sanctions don’t hurt him, they certainly do and he knows that.”