US 'deeply concerned' about uptick in Ukraine fighting

Washington : The United States declared itself "deeply concerned" Tuesday about renewed fierce fighting between Russian-backed rebels and government forces in eastern Ukraine, demanding a ceasefire. 

The industrial hub of Avdiivka came under an unexpected assault on Sunday from insurgents seeking to wrest back territory controlled by Kiev, and combat has continued for three days.

State Department spokesman Mark Toner said dozens of Ukrainian troops were killed, along with 10 civilians. 

Some 17,000 civilians, including 2,500 children, were also left without water, heat or electricity, according to the spokesman.

"To avert a larger humanitarian crisis, we call for an immediate, sustained ceasefire and full and unfettered access for OSCE monitors," he said.

The Organization for Security and Cooperation in Europe is responsible for monitoring ceasefire violations in the three-year-old conflict.

The State Department is still in transition, with President Donald Trump's secretary of state-designate Rex Tillerson yet to gain Senate confirmation.

Tillerson formerly had close ties with Moscow as chief executive of the US oil giant ExxonMobil, and Trump has frequently said that he wants to mend fences with Russia's President Vladimir Putin.

But Washington's European allies remain very concerned about Russian provocations on NATO's eastern flank and its interventions in the former Soviet republics Moscow still sees as within its sphere of influence.