SEOUL (Reuters) - North Korea test-fired a battery of short-range missiles on Friday in what analysts said was a show of the reclusive state’s anger at Washington and the new conservative government in Seoul.

North Korean soldiers talk on the northern part of the Joint Security Area at the truce village of Panmunjom in the demilitarized zone in Paju, 42 km (26 miles) northwest of Seoul, as a group of journalists attend a media tour organised by the United Nations Command March 26, 2008. REUTERS/Lee Jae-Won

The launch comes a day after the North expelled South Korean officials from a joint industrial complex north of the border, after Seoul told its destitute neighbor to clean up its human rights and stop dragging its feet in nuclear disarmament talks if it wants aid to keep its economy afloat.

A South Korean presidential spokesman told a news briefing the North had fired short-range missiles during a military exercise. Local news reports said the three were ship-to-ship missiles launched into the sea off the west coast.

“We believe the North does not want a deterioration of relations between the South and the North,” spokesman Lee Dong-kwan told reporters.

In Washington, White House spokesman Gordon Johndroe said missile testing was “not constructive” and should end.

“North Korea should focus on the denuclearization of the Korean Peninsula and deliver a complete and correct declaration of all its nuclear weapons programs, and nuclear proliferation activities and to complete the agreed disablement,” he said.

U.S. State Department spokesman Sean McCormack said North Korea’s tests had not broken any agreement but were not helpful. North Korea had made an “incredible amount of progress” in disabling its Yongbyon nuclear facility and he encouraged them to do more.

New South Korean President Lee Myung-bak has said he wants to end the free ride given to North Korea under 10 years of left-leaning presidents who gave billions in aid while asking little in return as long as there was stability.

Lee’s government has said it is ready to invest heavily if the North meets conditions such as scrapping its nuclear arms program or returning the more than 1,000 South Koreans it kidnapped or kept in the country after the 1950-53 Korean War.

Pyongyang was basically sending two messages with the launch, said Keio University Korea expert Masao Okonogi.

The first, aimed at the United States, showed the North’s disfavor with Washington’s pressure to come clean on uranium enrichment and ties with Syria. The second was a riposte to the Lee government’s policy shift, the Tokyo-based analyst said.

“They are warning Seoul not to go back on things agreed between the North and the South,” Okonogi said.

North Korea also threatened the South Korean navy, saying its patrols in disputed waters off the west coast of the peninsula could lead to battle. North Korea’s KCNA news agency described the patrols as the “reckless military provocations of the South Korean military warmongers.”

North Korea has more than 1,000 missiles, at least 800 of them ballistic, that can hit all of South Korea and most parts of Japan, experts have said. Its launches often coincide with periods of political tension.

At about the same time as the launch, North Korea’s official media fired a rhetorical volley at the United States, blaming it for pushing into deadlock six-country talks aimed at ending the North’s nuclear arms plans.

“If the United States continues to delay the resolution of the nuclear problem by insisting on something that doesn’t exist, it could have a grave impact on the disablement of the nuclear facility that has been sought so far,” KCNA quoted a Foreign Ministry spokesman as saying.

Pyongyang began disabling its Soviet-era nuclear plant late last year as part of a deal with regional powers in return for aid and an end to international isolation. The process has reached a stage where it would likely take North Korea at least a year to get its Yongbyon nuclear plant running again, South Korean officials said.

U.S. and South Korean officials said most steps to disable the reactor, a plant that makes nuclear fuel and another that turns spent fuel into arms-grade plutonium, are complete but a few elements have been delayed for technical reasons.

The agreement calls for the North to make a complete declaration of its nuclear weapons arsenal and answer U.S. suspicions of proliferating nuclear technology and having a clandestine program to enrich uranium for weapons.

“To make it clear, we have not enriched uranium or cooperated with any other country on nuclear projects. We have not even dreamed about it,” the North’s spokesman was quoted as saying.

North and South Korea held separate talks on Friday without incident on energy and economic aid the communist state receives in return for complying with the nuclear deal.