Russia is ready to back a draft UN Security Council sanctions resolution against North Korea over its third nuclear test if it focuses solely on its nuclear and missile programmes, a senior diplomat has said.

UN envoys said the United States and China have struck a tentative deal on a draft resolution to punish North Korea over the test.

Russia's Deputy Foreign Minister Gennady Gatilov said: "It will be acceptable to us if the restrictive measures do not go beyond the boundaries of missile and nuclear issues."

Russia holds the presidency of the 15-nation Security Council this month and is due to convene consultations on North Korea at the UN later today.

It is one of the five veto-wielding permanent members.

Security Council diplomats have said they would like to strengthen the provisions in previous sanctions, which were adopted after North Korea's 2006 and 2009 nuclear tests.

They related to the inspection and seizure of shipments of banned items and toughening financial restrictions.

North Korea's neighbour, China, has criticised the nuclear tests and said the council should respond "appropriately".

China's Foreign Ministry did not confirm it had reached a deal with the US.

Meanwhile, North Korea has said it will scrap the armistice ending the 1950-53 conflict with South Korea, if the South and US continue military drills.