ATLANTA — Delta Air Lines is trying to determine whether to push ahead with a combination with Northwest Airlines minus a prearranged deal between their pilots, a move that could change details of the deal, two people familiar with the discussions said Monday.

Delta and Northwest are looking at their route structures and how a combination now would affect them, given $100-a-barrel oil and a decision by both carriers to cut domestic capacity, one of the people said.

"When that happens, the merger details could change," the person said. "That will also affect the pilots."

There is no particular timeline or deadline for the airlines to decide whether to proceed with a deal, and things could still fall apart, the other person said. The people requested anonymity because of the sensitivity of the talks.

No meetings are scheduled this week between officials from both companies, though Delta's board met last week.

One option that remains on the table is a "light" deal between Delta Air Lines Inc. and Northwest Airlines Corp. in which they would combine some corporate functions but keep separate pilot ranks and operations, the people familiar with the talks said.