Russian Foreign Minister Sergei Lavrov urged Ukraine’s allies to back peace talks in Belarus and said any move by the government in Kiev to join NATO would upset those efforts. Ukrainian Defense Minister Valeriy Geletey said defenses must urgently be built to stop the advance of Russian troops. President Vladimir Putin sought to calm concern over remarks that his army could “take Kiev” in a matter of weeks.

“Unfortunately, the rise of the ‘party of war’ in Ukraine is being actively encouraged by Washington and some European capitals and more and more frequently from NATO headquarters in Brussels,” Lavrov told reporters today in Moscow.

Ukraine, the U.S. and Europe accuse Russia of dispatching soldiers and backing militias to open a new front in a conflict the United Nations estimates has cost at least 2,600 lives. Russia, which is facing further sanctions over its role in the unrest, has repeatedly denied involvement. U.S. President Barack Obama is heading to eastern Europe this week to reassure NATO members over their security.

The ruble slid to a record against the dollar for a third session as the intensified conflict raised the likelihood that Russia will face wider European Union penalties. It traded 0.2 percent weaker at 37.3840 as of 1:55 p.m. in Moscow.

Italy’s Foreign Minister, Federica Mogherini, who’s taking over as the European Union’s foreign-policy chief in December, said the 28-member bloc must apply pressure to find a political solution.

“We need to respond in the strongest possible way,” she told reporters in Brussels.