WASHINGTON (AP) — The Trump administration on Monday slapped sanctions on two South Sudanese officials accused of undermining peace efforts in the African nation.

The Treasury and the State Department announced they had added South Sudan’s defense minister and minister of cabinet affairs to a blacklist that freezes any assets they may have in U.S. jurisdictions. The State Department had warned of such consequences last week when it imposed sanctions on five other South Sudanese officials who it said were responsible for the abductions and likely murders in 2017 of two human rights activists.

Minister of Cabinet Affairs Martin Elia Lomuro and Minister of Defense and Veterans Affairs Kuol Manyang Juuk were targeted for being responsible or complicit in “actions or policies that threaten the peace, security, or stability of South Sudan, among other activities.”

“The United States stands ready to impose other measures against any who seek to expand the conflict and derail peace efforts in South Sudan,” the State Department said in a statement. “Efforts to undermine peace rob South Sudan of the security, stability, and confidence in government needed to negotiate and implement a lasting peace. The South Sudanese deserve leaders who are committed to laying the groundwork for a successful, peaceful political transition.”

South Sudan is slowly emerging from a five-year civil war that killed almost 400,000 people. A power-sharing agreement signed more than a year ago has been marked by delays and sporadic outbreaks of fighting in parts of the country. In November warring parties postponed the formation of a coalition government for the second time due to outstanding issues including security arrangements.

As a result of the delay, the U.S. has said it is reevaluating its relationship with the country. Last month it recalled its ambassador to South Sudan to Washington for consultations.