A U.S. official says the United States is seeking a U.N. resolution that would authorize sanctions against individuals undermining South Sudan's political stability and abusing human rights.

The official says the United States informed the Security Council on Tuesday that it will circulate a draft resolution to increase pressure on President Salva Kiir and former vice president Riek Machar to reach a peace agreement.

South Sudan has seen fighting between supporters of the two leaders since last December which has forced more than 1.7 million people from their homes.

The official, speaking on condition of anonymity because the council meeting was closed, says a sanctions regime would send a strong message that those most responsible for South Sudan's political and humanitarian crisis will be held accountable.