The US crackdown on Russian trade is working as Putin struggles to fund his war

• Trade with Russia has slumped in the first quarter amid tightening US sanctions, the Financial Times said.
• Companies in countries such as China are turning to costly underground channels to keep trading.
• The ruble has also risen in popularity, as other currencies are pulled back.

Moscow's key trade partners are getting cold feet, and it's causing export volumes to shrink as a US clampdown triggers reprisal fears among those who do business with the Kremlin.