Richard Anderson, Delta's new chief executive, was to meet Friday in New York with the Delta board of directors to seek permission to open formal talks with the two companies, The Atlanta Journal-Constitution said.
The move comes amid renewed speculation about a merger reportedly sparked by worsening conditions and slumping stock prices.
Word of a possible deal sent stocks of all three soaring -- Delta and Northwest up 36 percent and United 32 percent -- but all remained well below recent peaks.
Delta's pilot union chief advised members by letter that the long-rumored consolidation "may indeed at our door." Some skeptics called it a ploy to drive up stock prices to placate major investors.
Delta fought off a takeover bid by US Airways last year as the Atlanta-based carrier struggled through a bankruptcy restructuring.