“As Ukraine succeeds on the battlefield, Vladimir Putin is embarrassed and backed into a corner,” Peli told President Biden. “And I wonder, Mr. President, what you would say to him if he were thinking about using chemical or tactical nuclear weapons.” “Don’t. Don’t. Don’t. You’re going to change the face of war unlike anything since World War II,” Mr. Biden said. When Pelley asked what the consequences would be if Putin crossed that line, the president wouldn’t say. “Do you think I would tell you if I knew exactly what it was going to be? Of course, I won’t. It will be consequential,” Mr. Biden said. “They will become more outcasts in the world than ever before. And the extent of what they do will determine what response there is.” President Biden and Peli spoke at the White House, discussing a range of issues beyond the war in Ukraine, including the economy and the upcoming midterm elections. Mr. Biden also told Pelley about his efforts to prevent a strike on the national railroad. On Thursday, the president announced that a tentative agreement had been reached between the railroad and railroad workers’ unions after 20 hours of negotiations at the U.S. Department of Labor. “We combined business and labor,” the president told Pelley. “One of the things that happens in negotiations, especially if they’re as drawn out as these, is people say and do things where pride is also involved. And it’s awfully hard to back down from some of those things. So, what we did it was just to say, “Look, let’s take a look. Let’s take a look at what’s going on.’ was in the office today saying, “Well, we finally figured it out. That’s fair on both sides.” And it took this long to focus.” “The alternative was simply unthinkable,” Mr. Biden continued. “If, in fact, they had gone on strike, the supply chains in this country would have come to a standstill. We would have seen a real economic crisis.” The interview is Mr. Biden’s first meeting with 60 Minutes since his election to the presidency. 60 Minutes cameras were also with the president Wednesday as he toured the Detroit Auto Show. “60 Minutes” premieres its 55th season Sunday night on CBS at 7:30 p.m. ET and at 7 p.m. PT.