The visit comes as recent US strikes on a Syrian base were followed by hints of sanctioning Russia for supporting Assad.
From Press TV, Apr 11, 2017
The US has assured Ukraine that Washington will not consider any deal with Russia linking the fates of Ukraine and Syria, the Ukrainian president’s office says.
The office of Ukrainian President Petro Poroshenko announced the news in a Tuesday statement following a phone conversation between Poroshenko and US Secretary of State Rex Tillerson.
"Rex Tillerson emphasized that Washington will not allow any package deal as regards solution to the situation in Ukraine and Syria," the statement said.
Tillerson held talks with Poroshenko in the lead-up to his visit to Moscow. According to some media reports, Tillerson seeks to persuade Russia to abandon Syria during the visit.
The news comes amid Kiev’s concerns about the prospect of a clandestine agreement between Washington and Moscow over Crimea and other disputed territories seized by Russian-backed separatists in 2014.