A diplomatic source in Washington says senior North Korean and U.S. officials held an informal contact in New York last month and discussed U.S. food aid to the North.

The source says the two sides checked each other's positions during the meeting. The source stressed the so-called New York channel between U.S. Special Envoy to the Six-Party Talks Clifford Hart and North Korea's deputy ambassador to the United Nations Han Song-ryol is always open.

Another source said that when Washington contacts Pyongyang via the New York channel, it always notifies South Korea, and Seoul is believed to have been informed about the New York meeting in July.

Japan's Kyodo news agency says that during the New York meeting, the U.S. urged North Korea to take concrete steps to halt its nuclear development program while the North asked for resumption of food aid.