The haunting warning from a nation whose friendship Russian President Vladimir Putin had nurtured over his 14 years in power came amid Western efforts to shore up backing for the besieged interim leaders in Kiev who toppled a Kremlin-backed regime last month.
Canadian Prime Minister Stephen Harper will be the first leader from the G7 group of top industrialised powers to meet interim president Oleksandr Turchynov in Kiev since Crimea staged a contentious March 16 independence vote that saw Russia formally stake its claim to the Ukrainian peninsula yesterday.
"The referendum in Crimea... Is a violation of international law and an attempt to splinter Europe," Frank-Walter Steinmeier told reporters after meeting Ukrainian Prime Minister Arseniy Yatsenyuk.
The show of diplomatic solidarity may play an important psychological role in Kiev as it faces new rounds of pressure by Russia that include open threats to throw Ukraine's wheezing economy into convulsion by raising its gas rates and demanding colossal payments for disputed debts it could ill afford.