In an effort to deescalate tensions, North Korea said Saturday it was willing to suspend nuclear tests if the United States agreed to call off annual military drills held jointly with South Korea, but Washington rejected the proposal as a veiled threat.

The United States often conducts large-scale military exercises alongside South Korean armed forces in a show a strength that North Korea deems as provocative.

"The message proposed (that) the U.S. contribute to easing tension on the Korean peninsula by temporarily suspending joint military exercises in South Korea and its vicinity this year," KCNA news agency said in a report.

State Department spokeswoman Jen Psaki said the nuclear tests and military exercises were separate issues. "The DPRK statement that inappropriately links routine US-ROK exercises to the possibility of a nuclear test by North Korea is an implicit threat," Psaki told reporters traveling with Secretary of State John Kerry in Europe.

Relations between Washington and Pyongyang have been heavily strained in recent months after the U.S. accused North Korea of being behind a hacker attack on the Sony corporation and imposed new sanctions.

However, according to Japanese media, new secret talks regarding North Korea's nuclear program are set to begin soon.

South Korean President Park Geun-hye said Monday she was open to holding a summit meeting with North Korean leader Kim Jong Un without any pre-condition.

"My position is that to ease the pain of division and to accomplish peaceful unification, I am willing to meet with anyone," Park said. "If it is helpful, I am up for a summit meeting with the North. There is no pre-condition." Park's statement comes on the heels of North's leader Kim New Year's address where he expressed a willingness to participate in a high-level summit. 

North Korea has conducted three nuclear tests, the last in February 2013, and is under U.N. sanctions for defying international warnings not to set off atomic devices in pursuit of a nuclear arsenal.

It often promises to call off nuclear and missile tests in return for comparable steps by Washington to ease tensions. It reached such a deal in February 2012 with the United States for an arms tests moratorium only to scrap it two months later.

The United States and South Korea have carried out the joint military exercises for roughly 40 years, including the period where South Korea was ruled by a military dictatorship. The United States and South Korea have argued that the annual drills, which sometimes involve U.S. aircraft carriers, are purely defensive in nature.