WILLIAM BRANGHAM: Yesterday brought another low point between the United States and Russia, as Vladimir Putin elaborated on his demand that the U.S. reduce its staff in Russia by hundreds of personnel.
It's the latest diplomatic flash point in a tense relationship that President Trump and Putin had sought to improve.
Special correspondent Nick Schifrin reports.
NICK SCHIFRIN: This weekend on the Neva River in St. Petersburg, Russia celebrated its global naval ambitions. President Putin hailed thousands of Russian sailors lined up on ships and submarines. He said his hopes for a revamped, reenergized navy had been realized. And he admitted his hopes for a better relationship with the United States had been dashed.
PRESIDENT VLADIMIR PUTIN, Russia (through interpreter): We had waited quite a long time and thought something might change for the better. We had hoped that the situation will somehow change, but apparently, if it changes, it won't be soon.
NICK SCHIFRIN: On Friday, the Russian government ordered the closure of this U.S. Embassy Moscow storage facility. Today, American workers packed it up. The Russian government also ordered the closure of this country home used by U.S. diplomats, and an unprecedented, even stunning reduction in us staff, from more than 1,300 to 455.
On state TV, Putin said he hoped he wouldn't have to deliver further punishment.
VLADIMIR PUTIN (through interpreter): We certainly have something to respond with and restrict those areas of joint cooperation that will be painful for the American side, but I don't think we need to do it.
NICK SCHIFRIN: Dmitri Trenin runs the Carnegie Center in Moscow.
DMITRI TRENIN, Carnegie Center: He cares about the relationship. he is not going to burn his bridge, although it may be a very rickety bridge, that he has established with President Trump.
NICK SCHIFRIN: Just 300 miles away from St. Petersburg, Vice President Pence visited NATO and E.U. member Estonia. He praised Estonia's commitment to NATO and called the Russian government's cap on staff drastic. And, like Putin, he said he hoped things didn't get even worse.
VICE PRESIDENT MIKE PENCE: A better relationship and the lifting of sanctions will require Russia to reverse the actions that caused the sanctions to be imposed in the first place.
NICK SCHIFRIN: Those actions include destabilizing Ukraine and hacking during the 2016 election. Most U.S. officials tell me they want to see a robust response to Putin's moves, and acknowledge these days are echoing the Cold War diplomatic tit-for-tats of the 1980s.
DANIEL FRIED, Atlantic Council: He wants to have a Cold War-type relationship? Let's remind him how this ended up.
NICK SCHIFRIN: Ambassador Dan Fried led the Obama administration's efforts last year to sanction Russia. Fried urges the administration to exploit the nearly unanimously passed congressional sanctions bill.
DANIEL FRIED: If the Russians are messing with us and trying a playbook from the Cold War, then, in general and without prejudice, let's implement those new sanctions with vigor. Let's lean forward and let's mean it.
NICK SCHIFRIN: But that is exactly the kind of response that Russians fear will exacerbate a conflict that's increasingly dangerous and increasingly poisoned by the U.S.-Russia investigation.
DMITRI TRENIN: Try to distinguish, or differentiate between the Russia story in the United States and the Russia policy of the United States, to make sure that the United States and Russia, who are adversaries at this point, do not become true enemies.
NICK SCHIFRIN: And that is something that neither side wanted, but looks increasingly inevitable.
For the PBS NewsHour, I'm Nick Schifrin.