Negotiations aimed at coaxing North Korea to scrap its nuclear weapons ended without progress on Friday, with Washington and Pyongyang blaming each other for betraying expectations and no date set for fresh talks, Reuters repored. The six parties -- the two Koreas, the United States, Japan, Russia and host China -- agreed only to "reconvene at the earliest opportunity," according to a statement from the chief Chinese negotiator Wu Dawei. Envoys had sought to flesh out a September 2005 agreement that promised North Korea aid and security guarantees in return for nuclear disarmament, but Pyongyang was preoccupied only with getting U.S. financial curbs against it lifted. Chief U.S. negotiator Christopher Hill said that, after hopeful informal contacts, it became clear that his North Korean counterpart, Kim Kye-gwan, lacked the backing to formally deal on anything but the financial standoff. "Alas, by the end of the week, it was clear the DPRK ... team did not have the instructions that they needed to go forward and to agree to the proposals," Hill told reporters. "They were not prepared to engage on the actual agreement."