WASHINGTON—President Joe Biden has threatened to impose devastating sanctions on Russia if leader Vladimir Putin invades Ukraine, but some big companies and business groups are pushing the White House and lawmakers to be cautious. A trade group representing Chevron, General Electric, and other big U.S. corporations that do business in Russia is asking the White House to consider allowing companies to fulfill commitments and to weigh exempting products as it crafts any sanctions. At the same time, big energy companies are pushing Congress to limit their scope and time frame. The Biden administration and Congress need to “get the details right in case they must follow through on the threat of sanctions,” Jake Colvin, president of The National Foreign Trade Council, told Reuters Monday. “Those details should include consideration of safe harbors or wind-down periods to enable companies to fulfill existing contracts and obligations, as well as carve-outs for lifesaving …