The conflict, which has killed at least 10,000 people, as well as Russia's annexation of Crimea from Ukraine in 2014 have pushed ties between Moscow and the West to their lowest point since the Cold War.
Tillerson's support for restoring Ukraine's territorial integrity came as a welcome relief to officials in Kiev, who feared the Trump administration would look the other way on Russian intervention in order to negotiate a deal with Moscow over the crisis in Syria. A few days ago, Mr. Tillerson announced he was appointing a new special envoy, Kurt Volker, an experienced diplomat, to help settle the dispute in Ukraine in part at the request of Mr. Putin.
Volker will "coordinate all State Department efforts to bring a resolution to the conflict created when Russian Federation invaded Crimea and later eastern Ukraine", Tillerson spokesman R.C. Hammond told Bloomberg.
Ukrainian experts believe that the Secretary of state intends to inform the Ukrainian leadership about the results of the negotiations of the US President Donald trump with the President of Russia Vladimir Putin, as well as the results of the trilateral meeting of the leaders of Germany, France and Russia on the sidelines of the G20 summit in Hamburg.
"The US and European Union sanctions on Russian Federation will remain in place until Moscow reverses the actions that triggered these particular sanctions", Tillerson said at a briefing after a meeting with Ukrainian President Petro Poroshenko in Kiev.
When pressed on the question, Mr. Tillerson used language he had used Friday night, as the meeting in Hamburg broke up, calling the election hacks the "first topic for discussion". "We firmly adhere to our commitments", he said. "And so I think that was about the way we expected the conversation to go".
Rasmussen has stressed that Ukraine's security is NATO's security, and "many of the challenges we face today - from election interference to cyber security - are areas where Ukraine has significant experience in countering".
The top United States diplomat also said Washington would explore ways of changing the status quo in the Ukraine crisis, and said Russian interference in the 2016 USA presidential election has prevented better ties with Moscow. "We have to find a way to begin to address that, and it's not going to be only about Russian Federation, it's going to be about global engagement as well".