US Defence Secretary: 'Russians are way off track in Syria'
World powers have agreed to seek a nationwide "cessation of hostilities" in Syria, to begin in a week's time.
The halt will not apply to the battle against jihadist groups Islamic State and al-Nusra Front.
The plan was announced by Russian Foreign Minister Sergei Lavrov and US Secretary of State John Kerry in Munich, Germany.
However US Defence Secretary Ash Carter told the BBC's Jonathan Beale it remained to be seen whether Russia would implement the agreement.
12 Feb 2016