N.Korea to boost nuclear weapons capability

SEOUL (Reuters) - North Korea said on Tuesday it would boost its nuclear weapons capability because U.S. President Barack Obama was determined to ignore its calls for peace and bring it down by military force.

North Korea said this week that it had put its army on full combat alert as U.S. and South Korean forces began joint military drills involving nearly 40,000 troops, an annual event that draws anger from the North but typically results in no major incidents.

"The U.S. is leaving no means untried to bring down the DPRK (North Korea) including military threat, economic sanctions and ideological and cultural poisoning," the North's KCNA news agency quoted an unnamed foreign ministry spokesman as saying.

"(The North) will continue bolstering up its nuclear deterrent as long as the U.S. military threats and provocations go on," the spokesman said.

The North has come under pressure to return to six-party disarmament-for-aid nuclear talks because of U.N. sanctions imposed after a May 2009 nuclear test and prodding by its major ally and the host of the talks, China.

Sanctions have dealt a blow to its wobbly economy, and a botched currency move late last year has sparked inflation and rare civil unrest.

The two Koreas are technically still at war because their 1950-53 conflict ended with an armistice and not a peace treaty.

The North said at the weekend that any talks on denuclearising the Korean peninsula would "naturally come to a standstill" because of the drills. North Korea conducted live fire exercises near sea borders with the South earlier this year.

(Reporting by Jack Kim; Editing by Jonathan Hopfner)