British foreign secretary Philip Hammond accused Russian President Vladimir Putin on Sunday of acting like a "tyrant" over Ukraine, but said Kiev's forces could not defeat Russia's army and that only a political solution could end the bloodshed.
“Ukrainians can’t beat the Russian army, that’s not a practical proposition. There has to be a political solution,” he told Sky News.
“This man has sent troops across an international border and occupied another country’s territory in the 21st century acting like some mid-20th century tyrant. Civilised nations do not behave like that,” he added.
Russia denies Western and Ukrainian accusations that it is actively supporting pro-Russian separatists in eastern Ukraine by sending regular troops and weapons into the region.
Mr Hammond's comments came a day after Germany's Chancellor Angela Merkel said sending arms to help Ukraine combat the separatists would not solve the crisis there, drawing sharp rebukes from US politicians.
Mr Hammond said Britain was not planning to arm Kiev's forces but spoke out strongly in favour of renewing European Union economic sanctions on Russia.
He also said Russia must withdraw from Crimea, the Black Sea peninsula Moscow annexed from Ukraine last March, and start to respect international law.
Minsk summit
Germany’s government says a top-level summit to discuss the crisis in Ukraine is being planned for the coming week.
Chancellor Angela Merkel's spokesman says preparations are underway for her to meet Mr Putin, Ukrainian president Petro Poroshenko and French president Francois Hollande in the Belarusian capital Minsk on Wednesday.
German government spokesman Steffen Seibert said the decision follows an "extensive" phone call Sunday morning between the four leaders, during which further measures for a peace plan were discussed.
More than 5,000 people have been killed in eastern Ukraine since the conflict began there last April following the ousting of the country's Russian-backed president, Viktor Yanukovich, during mass street protests in Kiev.
Agencies