Negotiating with another country’s territory as collateral has a long history—the most obvious example is from 1938.
Last Friday, Vladimir Putin called Barack Obama to discuss Ukraine, although what was said is different from what was heard. Analyzing the discrepancies between the White House and Kremlin press releases of these calls has become a booming industry and usually you would never guess that the reports are about the same conversation. The White House report mentions “constitutional reform and democratic elections” and Russia pulling back its troops from eastern Ukraine. The Kremlin summary refers to the “rampant extremists” in Kiev and adds the separatist Moldovan region of Transnistria to the conversation in a blatant threat to up the ante once again.