CIA Director William Burns said Russian President Vladimir Putin is too confident that he can defeat Ukraine as China considers providing lethal military aid to Moscow.

The Russian leader does not appear to be backing away, Burns told CBS Face the Nation when asked if he sees any signs that Putin will come to the realization that he cant win the conflict.

I think Putin is, right now, entirely too confident of his ability, as I said before, to wear down Ukraine, to grind away and thats what hes giving every evidence that hes determined to do right now, Burns told CBS Margaret Brennan in the interview, which aired Sunday.

In a separate interview with Face the Nation, former Secretary of State Condoleezza Rice said the U.S. should do everything that we can to convince Putin he is wrong in thinking time is on his side and that support for Ukraine from Europe and the U.S. will erode.

Meanwhile, U.S. officials have expressed concern over the potential of China sending lethal military aid to Moscow. Belarusian President Alexander Lukashenko, a Putin ally, is due to visit Beijing later this week.

Theres no foreign leader whos watched more carefully Vladimir Putins experience in Ukraine, the evolution of the war, than Xi Jinping has, Burns said.

Burns added that Xi was likely surprised by the Russians poor performance on the battlefield.

I think [he was] surprised also by the degree of Western solidarity and support of Ukraine, Burns said. In other words, the willingness of not just the United States, but our European allies as well to absorb a certain amount of economic cost in the interest of inflicting greater economic damage on Russia over time.

The U.S. so far has been the largest bilateral spender on Ukraine, committing over 73 billion ($77 billion) from Jan. 24, 2022, to Jan. 15 of this year, according to the Kiel Institutes Ukraine Support Tracker .

Burns said that he previously visited Russian spy chief Sergei Naryshkin under President Joe Biden s orders to get the message across to Moscow, including Putin, about the severe consequences the country would face should Russia ever choose to use a nuclear weapon of any kind.

And I think Naryshkin understood the seriousness of that issue and I think President Putin has understood it as well, Burns added.

Russias war in Ukraine hit its one-year mark on Friday. Last week, Putin gave his long-anticipated state of the nation address , where he announced Moscow was withdrawing from the New START nuclear arms control treaty signed with the U.S. in 2010.

Biden called Putins announcement a big mistake, and Bonnie Jenkins, U.S. undersecretary for arms control and international security, said Monday that it showed the world Russia is not a responsible nuclear power.

Rice urged 2024 presidential hopefuls to grasp the larger implications of the Ukraine war, which she explained is not just about Ukraines independence, but also defending a rules-based system.

Former President Donald Trump , the first GOP candidate to announce a 2024 campaign, earlier this month told talk radio host Hugh Hewitt: This thing has to stop, and its got to stop now. And its not going to stop if we continue to just load something up, referring to aid to Ukraine.

Rice warned future presidential candidates that big conflicts like the Ukraine war always come home.

If the American people see a world in which Vladimir Putin and Xi Jinping have won this engagement, this first volley, if you will, in the largest strategic picture, and they see that Ukrainian independence has been extinguished, and they know that the United States could have done something about it, I dont think thats going to be a very good message for a future president to have to deliver, she said.