The North Korean Foreign Ministry struck back at U.S. sanctions Wednesday, calling them "a hostile act" and saying that the country won't surrender. 

North Korea also said that Washington was trying to "to bring us to our knees" through the sanctions. The Foreign Ministry added it would not hesitate to defend itself if its sovereignty is threatened. 

President Donald Trump last week signed executive orders to initiate sanctions against North Korea over its nuclear and missile programs. 

"The actions and policies of the government of North Korea continue to pose an unusual and extraordinary threat to the national security, foreign policy, and economy of the United States," the executive order said. 

The statements by the Foreign Ministry contrast the recent friendly correspondence between Trump and North Korea leader Kim Jong Un.  Trump recently said he received a "beautiful letter" from Kim and that the North Korean leader had wished him a happy birthday. In return, Trump sent a letter back to Kim, which the North Korean leader called "excellent."

North Korea and the U.S. have undergone multiple rounds of diplomatic talks over the country's nuclear program. The U.S. wants North Korea to denuclearize, while North Korea wants the sanctions lifted.

Trump and Kim met in Singapore in June 2018 to discuss denuclearization and sanctions, as well as returning the remains of American troops. In February, the two sides met again in Hanoi, Vietnam, but failed to reach a deal.

Trump is scheduled to make a trip to South Korea on Saturday.

North Korea and South Korea are technically still at war with each war each other, as the Korean War in 1953 ended in a truce not a peace treaty.