U.S. Secretary of Defense James Mattis visited Ukraine on Thursday, and used that opportunity to reaffirm that the United States would continue to support the nation against Russian aggression.

Mattis first attended the Ukranian Independence Day Parade in Kiev, before attending meetings with his Ukrainian counterpart, Defense Minister Stepan Poltorak, as well as President Petro Poroshenko.  After the meetings, Mattis appeared alongside Poltorak for a joint press briefing, in which Mattis accused Russia of failing to honor the Minsk ceasefire agreement that aimed to quell the ongoing conflict in Eastern Ukraine between Russian backed separatists and the local government.

Have no doubt, the United States stands with Ukraine. We support you in the face of threats to sovereignty and territorial integrity, to international law, and to the international order writ large.” He said.  “We do not, and we will not, accept Russia’s seizure of Crimea and despite Russia’s denials, we know they are seeking to redraw international borders by force, undermining the sovereign and free nations of Europe.”

Mattis went on to declare that the United States would continue to push Moscow to live up to its obligations per the Minsk agreement, which was signed in 2014 but has yet to see Russia fully implement it.