MIAMI (AP) — Senator Marco Rubio says the U.S. must respect a weekend referendum by the people of Colombia who rejected their government’s peace agreement with leftist rebels.

In a statement Rubio said that the Colombian people should ultimately decide how the decades-long war with the Revolutionary Armed Forces of Colombia comes to a close. He added that such an agreement must “be fair” to those affected by the U.S.-designated terrorist organization.

Rubio, who sits on the Senate Committee on Foreign Relations, announced his remarks after Colombians rejected the deal Sunday. The final results showed that 50.2 percent of Colombians opposed the deal while 49.8 percent favored it.

Colombian president Juan Manuel Santos says he will keep a cease-fire in place and will continue with his efforts to end the war.