U.S. Secretary of State John Kerry said on Saturday that the United States and Russia had agreed to exchange information about the situation on the Russia-Ukraine border.
Ukraine's military accused Russia on Friday of sending a column of 32 tanks and truckloads of troops into the country's east to support pro-Russian separatists fighting government forces.
"Suffice it to say that we do have some disagreements about some of the facts on the ground with respect to Ukraine. We have agreed to exchange some information between us regarding that. We have also agreed this is a dialogue between us that will continue," Kerry told reporters in Beijing.
But he seemed to suggest new Western sanctions against Russia were not imminent.
"The choices Russia makes will decide what happens with respect to sanctions in the long run here," Kerry said, adding he hoped a ceasefire agreement in Ukraine would remain viable.