In the case of North Korea, the United States and the allies will target not only missiles and nuclear materials but also narcotics, which Washington says is Pyongyang's main source of hard currency to fund its weapons development.

The United States discussed the measure at the meeting last week in Madrid of 12 countries that are joining efforts to prevent the spread of weapons of mass destruction. The White House has decided to concentrate its efforts on combining its intelligence with the creative use of the allies' national laws, rather than rewriting the existing international laws that respect the freedom of the seas, the newspaper said.

The White House is stepping up its efforts to form a coalition of nations that would allow suspect ships to be boarded and aircraft to be forced down the moment they slip into any cooperative country's waters or airspace. The Pentagon and the State Department are working on the details of the measure.

Japan's and Australia's recent recent buildups in surveillance against North Korean ships could be explained in this context, the report said.

A related action plan will be drawn up at the meeting of the ASEAN Regional Forum opening Wednesday in Phnom Penh, Cambodia, with foreign ministers from the United States, South Korea, Japan, China, Russia and ASEAN member countries attending. The plan is designed to spur more intelligence-sharing between the countries, stimulate cooperation between judicial authorities, guarantee the safety of transportation by sea, strengthen immigration management and support the U.S. armed forces' training against terrorism.

(Joo Yong-jung, midway@chosun.com )