KYIV, Ukraine (AP) — Clinching a deal to end the Russia-Ukraine war “is far too complex to be done quickly,” a senior Kremlin official said Wednesday, as the U.S. labors to bring momentum to peace efforts and expresses frustration over the slow progress.

U.S. Secretary of State Marco Rubio welcomed the signing of the minerals agreement between Ukraine and the United States, referring to it as an important step toward ending the Russo-Ukrainian war. — Ukrinform.