Northwest Airlines, the subsidiary of Atlanta-based Delta Air Lines, is seeking to delay or cut back long-coveted US-China service due to poor market conditions, AP reported. It said earlier this month that it was seeking to delay proposed daily Seattle-Beijing service by a year from March 2009 to March 2010 and delay startup of Detroit-Shanghai nonstop service by more than two months from 25 March to 3 June 2009.