KIEV, Ukraine (AP) — U.S. Secretary of State Rex Tillerson is in Ukraine to reaffirm American support as the country struggles with a Russia-backed insurgency in the east and attempts to crack down on corruption.

Tillerson meets Sunday with Ukrainian President Petro Poroshenko, just 48 hours after sitting in on President Donald Trump's first face-to-face talks with Russian leader Vladimir Putin in Germany.

His short visit to Kiev comes as the U.S. explores taking a greater role in a European-led effort to end the three-year conflict in Ukraine's east that has claimed around 10,000 lives. Russia annexed the Crimean Peninsula from Ukraine in 2014.

Tillerson has appointed a special envoy to examine possibilities for jump-starting implementation of a two-year-old peace roadmap known as the Minsk Agreement.

Speaking to a group of reform advocates at the U.S. ambassador's residence, Tillerson praised Ukraine's progress in combating corruption, increasing government transparency and collecting taxes but made clear that more must be accomplished.

"Ukraine has come a long way," he said. "We want to acknowledge that (but) we still have more to do and this is all about securing Ukraine's future: making the place attractive for investors, being attractive to their European neighbors."