The Philippines said Saturday it had impounded a North Korean vessel in response to tough new United Nations sanctions introduced in response to Pyongyang's recent nuclear and ballistic missile tests.

The 6,830-tonne cargo ship Jin Teng will not be allowed to leave Subic port, northeast of the capital Manila, where it had been docked for three days and its crew will be deported, presidential spokesman Manolo Quezon said on state-run radio station Radyo ng Bayan.

It was the first reported enforcement of the sanctions, the toughest to date, which were adopted late Wednesday by the UN Security Council.

"The world is concerned over North Korea's nuclear weapons programme and as a member of the UN, the Philippines has to do its part to enforce the sanctions," Quezon said.

A team from the UN is expected to inspect the ship in the port, located near a former United States naval base, foreign affairs spokesman Charles Jose said.

Jose told AFP the ship was impounded "in compliance with the UN resolution" regardless of the results of the inspections.

The Jin Teng, carrying palm kernels, was searched for the second time on Saturday, this time using electronic weapons sensors, coastguard spokesman Commander Armand Balilo told AFP, adding the 21 crewmen were "very cooperative".

Balilo said no explosives, drugs or banned substances have been found so far.

- Heightened tensions -

North Korea has no embassy in the Philippines. Its embassies in Thailand and Indonesia were unavailable for comment when contacted by AFP.

However, North Korean state media blasted the new round of sanctions again on Saturday, calling the UN resolution a "disgrace".

"It is a disgrace to the world community to allow such high-handed practice of the US and other big powers possessed of many satellites and nuclear warheads," read a statement published by the North's official KCNA news agency.

"We will resolutely use all means and methods to take powerful, merciless and physical counteractions against the hostile forces' anti-DPRK moves."

There are no other North Korean ships docked in Subic, according to the coastguard.

The Jin Teng arrived in the Philippines from Palembang, Indonesia Thursday afternoon, just hours after the latest sanctions were unanimously passed.

In response to the UN's move, Pyongyang fired six short-range missiles into the sea on Thursday, while North Korean leader Kim Jong-Un ordered its nuclear arsenal put on standby for pre-emptive use at any time.

Kim also warned that the situation on the divided Korean peninsula had become so dangerous that the North needed to shift its military strategy to one of "pre-emptive attack".

Washington downplayed Kim's threat as posturing.

"We have not seen North Korea test or demonstrate the ability to miniaturise a nuclear weapon and put it on an ICBM (intercontinental ballistic missile)," a US defence official told AFP.

Still, the official added, "our forces are ready to counter-eliminate strikes if necessary".

On Friday, the European Union also tightened sanctions against North Korea by adding 16 people and 12 entities to a list of some 60 individuals and groups who were hit with travel bans and asset freezes.

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