JP Morgan analysts outline potential retaliation by Russia if the G7 manage to put together a mechanism to cap the price of Russian oil:

• “The most obvious and likely risk with a price cap is that Russia might
  choose not to participate and instead retaliate by reducing exports.”
• “It is likely that the government could retaliate by
  cutting output as a way to inflict pain on the West. The tightness of
  the global oil market is on Russia’s side.”

Price impact:

• A 3 million-barrel output cut to daily supplies would push benchmark London
  crude prices to $190
• Worst-case scenario of 5 million could
  mean “stratospheric” $380 crude

Info comes via Bloomberg (gated)