The United States cast doubt on a report Wednesday that North Korea may declare itself a nuclear state in September unless progress is made in the current nuclear standoff.

During a regular briefing, State Department spokesman Richard Boucher dismissed the report as speculation, stating that he was unaware of any concrete evidence supporting the claim.

Citing unidentified diplomatic sources in Tokyo, Reuters news agency reported earlier in the week that the communist state was prepared to officially declare itself a member of the nuclear club unless the United States responds positively to its proposals for resolving the nuclear row.

In recent weeks, international diplomatic efforts to set up a new round of talks have swiftened pace. At the center of those efforts is China, which came up with a compromise proposal of holding another three-way meeting followed by expanded multilateral talks.

The United States appears to have endorsed the Chinese proposal, and is currently waiting for the North's response to the offer.