 Turkey accused the US of dragging its feet and sabotaging the implementation of the roadmap, vowing to never enter into a similar deal in the future.Relations between Turkey and the SDF became increasingly hostile in mid 2019, with the SDF joining forces with the Syrian Government to repel a Turkish-opposition military operation near Tell Rifaat.The deputy secretary of defense for the Middle East, Michael Mulroy said at the Council on Foreign Relations that the United States cannot carry out its strategy in Syria without partners such as the mostly Kurdish SDF, who "bore most of the burden in destroying the Islamic State's caliphate".