US President Barack Obama is considering additional sanctions against the Democratic People's Republic Korea (DPRK) in response to its nuclear test, his aide said Wednesday.

Pyongyang's nuclear test "is of huge priority to the president," Ben Rhodes, Obama's deputy national security adviser, told a press briefing, adding that Obama is reaching out to leaders of South Korea and Japan after the incident.

The DPRK's recent announcement of successful hydrogen-bomb test was disputed by the United States, which said initial analysis indicated that the nuclear test was "not consistent" with a hydrogen bomb.

Explaining why Obama did not mention DPRK in his State of the Union address, Rhodes said that is because the president did not want to give DPRK "the attention it wants."

On Tuesday, US House of Representatives passed legislation to impose harsher sanctions against the DPRK.

The measures include sanctions on those engaging in transactions with the DPRK related to weapons of mass destruction, arms, luxury goods, money laundering, counterfeiting and human rights abuses.

It also gives Obama the authority to sanction those engaging in financial transactions to support DPRK's banned activities and development of cyber threat industry.