The United States on Friday froze the assets of a bank of the Democratic People's Republic of Korea (DPRK), further beefing up its financial sanctions against the country.

The latest US sanctions against Pyongyang targeted the Amroggang Development Bank, which was controlled by the DPRK's Tanchon Commercial Bank, an institution blacklisted and sanctioned by Washington.

The Amroggang Development Bank is "a proliferator of weapons of mass destruction," the US Department of Treasury said in a statement.

"As long as North Korea continues to try to evade sanctions and obscure its illicit proliferation transactions, we will take steps to combat that activity and protect the integrity of the international financial system," Stuart Levey, undersecretary of the Treasury Department, said in the statement.

US Secretary of State Hillary R. Clinton said on Wednesday that the United States will not have normal ties with the DPRK or relax its sanctions against the country until Pyongyang abandons nuclear arms.

"Current sanctions will not be relaxed until Pyongyang takes verifiable, irreversible steps toward complete denuclearization," Clinton said in a policy address to the United States Institutes of Peace.