London (CNN Business) 1. Oil prices: Oil is rallying as global tensions with Iran continue to escalate, sparking concerns about supply.

Brent crude, the global benchmark, rose 2.3% on Monday to $63.91 per barrel. US oil prices are up 2.1%.The gains follow news on Friday that Iran seized a British tanker in the Strait of Hormuz.

Britain has warned that it will take "robust" action if Iran does not release the ship, and the government's emergency response committee is meeting Monday.

The episode comes after Britain detained an Iranian tanker in waters off Gibraltar.

The United States and Iran are also engaged in a tense standoff. The United States last week claimed to have downed an Iranian drone, almost exactly one month after Iran shot down a US drone.