By Nandita Bose and Steve Holland WASHINGTON (Reuters) -Russia is laying the groundwork for the annexation of Ukrainian territory and is installing illegitimate proxy officials in areas there under its control as it seeks to exert total control over its gains in the east, the White House said on Tuesday. Unveiling what he said was U.S. intelligence, John Kirby, the chief National Security Council spokesman, told a White House news briefing that the Russians are preparing to install proxy officials, establish the rouble as the default currency and force residents to apply for citizenship. “We h…