As reported by Censor.NET citing RIA Novosti news agency, this was said by spokesperson for Russian Foreign Ministry Maria Zakharova.
"I see it not as an ultimatum, but as a political statement, as a saber rattling before talks. Such approach is quite usual for Washington," Zakharova said commenting on Tillerson's statement that US wanted to relieve the suffering of the Syrian people while Russia could be a part of that future or maintain its alliance with Syria and Iran.
Tillerson arrived in Moscow on Tuesday to hold talks with Russian Foreign Minister Sergei Lavrov.
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