SEOUL (Reuters) - North Korea said on Friday it was being forced to "reexamine" its nuclear program because of fresh signs the United States remains hostile towards the country, indicating it will step up defiant efforts to boost its nuclear arsenal.

The new leadership of North Korea, headed by the third generation of the Kim family, reinforced its control on the reclusive state this week by further promoting its young leader Jong-un and purging a top general who was seen as opposing his reforms.

The North has denied in recent months that it was preparing to conduct a third nuclear test, after a failed rocket launch widely seen as a long-range missile test in disguise, which effectively scrapped a deal on moratorium on such tests reached with Washington in February.

"The consistent hostile policy towards the DPRK pursued by the U.S. is giving rise to the evil cycle of confrontation and tensions on the Korean Peninsula, making the prospect of denuclearizing the peninsula all the more gloomy," the North's unnamed Foreign Ministry spokesman said.

DPRK is short for the North's official name, the Democratic People's Republic of Korea.

"The situation compels the DPRK to totally reexamine the nuclear issue," the spokesman said in comments carried by the official KCNA news agency.

"Without the U.S. fundamental repeal of its hostile policy toward the DPRK first, it will be completely impossible to settle the issue of ensuring the lasting peace and stability on the Korean Peninsula."

North Korea this week accused the United States of masterminding a sabotage on the statues of its dead leaders in Pyongyang by sending a defector who had fled to the South back into the country to destroy them.

(Reporting by Jack Kim; Editing by Daniel Magnowski)