North Korea sent a rare letter of protest to the U.S. House of Representatives on Friday, May 12 warning that a new package of tougher sanctions would only spur its development of nuclear weapons, North Korea's state media reported.

The protest was lodged by the recently revived Foreign Affairs Committee of North Korea's Supreme People's Assembly, which said the U.S. House of Representatives was "obsessed" with a sense of disapproval and warned it of dire consequences, Reuters reports.

"The U.S. House of Representatives should think twice," the committee said in its letter, a copy of which was published by the KCNA state news agency.

Tension has been high for weeks over North Korea's nuclear and missile development and fears it will conduct a sixth nuclear test or test-launch another ballistic missile in defiance of U.N. Security Council resolutions.

The House of Representatives overwhelmingly approved legislation this month to tighten sanctions by targeting North Korea's shipping industry and companies that do business it.

The U.S. legislation was intended to cut off supplies of cash that help fund North Korea's nuclear program, and increase pressure to stop human rights abuses such as the use of slave labor, the bill's sponsor said.