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 yesterday.

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."

Overarching issues like the combined company being based in Atlanta, Delta Chief Executive Richard Anderson being the head of the combined entity and the airline being called Delta are not likely to change, the person said.

The other person said 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 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 of the people familiar with the talks said.