The six-party negotiations, aimed at persuading the reclusive communist state to abandon its nuclear program, resumed in the Chinese capital earlier in the day after a 13-month standoff.
The source said, "They [North Korea] want the sanctions to be lifted, and diplomatic relations with the United States to be established."
Following North Korea's October 9 announcement that it had conducted its first nuclear bomb test, the UN Security Council passed a special resolution October 14 blocking all deliveries of military equipment and supplies to the country.
Last year the U.S. accused North Korea of printing fake dollars and laundering money through foreign banks, and ordered a Macao-based bank to freeze North Korean accounts holding $24 million.
The six-party talks, involving North and South Korea, Russia, Japan, China and the U.S., were initially launched in 2003 after Pyongyang withdrew from the Nuclear Non-Proliferation Treaty.
At the September 2005 talks round, Pyongyang agreed to abandon its nuclear program in exchange for aid and security guarantees, but later boycotted further meetings, in protest against Washington's financial sanctions.
North Korea, which does not have diplomatic relations with the U.S., agreed to return to the talks table after a long pause, but insisted that the agenda focus on the financial restrictions.
Talks on unfreezing Pyongyang's bank accounts are expected begin in Beijing Tuesday, after the arrival of North Korea's financial delegation, led by the country's Central Bank chief.
