The European Union agreed a raft of new sanctions on Monday against North Korea in retaliation for the country's nuclear test last week which it condemned again in the strongest possible terms.

The measures range from additional financial sanctions to travel bans and asset freezes against individuals and are intended to bolster the international regime against the proliferation of nuclear weapons, a statement said.

The number of people subject to a travel ban and asset freeze was put at 26 while the number of entities targetted was 33, it said, without giving the specific increase in either category.

Among other steps, the EU banned the export and import of certain types of aluminium which Pyongyang could use in its ballistic missile systems while trade in North Korean bonds was also barred.

Trade in gold, precious metals and diamonds with North Korean public bodies was halted along with delivery of new banknotes and coinage to the North Korean central bank.

North Korean banks will not be allowed to open new branches in the EU or establish joint ventures with European financial institutions which in turn will be barred from opening offices and subsidiaries in the isolated country.

Ministers said in the statement they were determined to "consider further restrictive measures in consultation with key partners."

"It is a tough package that aims to mark our opposition to the nuclear test" conducted by Pyonyang on February 12, said a senior EU diplomat who asked not to be named.

The UN Security Council on January 22 ordered increased sanctions against North Korea, adding its state space agency, a bank, four trading companies and four individuals to an existing UN sanctions list.

A separate EU statement reiterated the EU's condemnation of the test "in the strongest terms," as violating North Korea's international obligations under UN resolutions, passed after previous nuclear tests in 2006 and 2009, and ballistic missile launches.

The increased risk posed by the test "warrants further robust and effective measures by the international community aimed at preventing (Pyongyang) from pursuing its nuclear and ballistic (missile) programmes."

At the same time, the EU called on North Korea to "re-engage constructively with the international community" so as to help resolve tensions, it said.

EU figures show trade with North Korea to have been almost minimal over the past several years, with the isolated country depending heavily on its giant neighbour China to help support its struggling economy.