Human markets: oil at $110 as US embassies warn of closed airspace.

What happened

On Friday 16 October, Brent crude touched $110 a barrel for the first time since May. It closed at $109.86, up 3.7% on the day and its highest close since 19 May. US crude closed at $101.41, up 10.4% for the week. On Monday, Bloomberg had Brent holding near $110.

On Sunday, US embassies in 12 countries issued security alerts: Israel, Saudi Arabia, Iraq, Lebanon, Jordan, Qatar, Bahrain, Kuwait, Oman, the UAE, Yemen and Iran.

"Be aware of potential flight cancellations, airspace closures, and travel disruptions," the alerts say. They tell Americans to "develop contingency plans in advance."

The alerts cite Houthi attacks on Saudi Arabia and warn that "the hostilities have the potential to escalate rapidly beyond that immediate area." They add that Iran and its allies may target US interests, including "U.S. businesses and other institutions."

On Friday, a Saudi-led coalition said it destroyed a ballistic missile aimed at Yanbu, the port Saudi Arabia uses to bypass the Strait of Hormuz. Iran says it is stepping up strikes in response to a US blockade of its ports. Kpler, which tracks tankers, wrote: "Intensified Iranian attacks drove Gulf crude flows sharply lower."

On 14 October, Israel's Channel 14 reported that Israel had raised its security alert to the "highest possible level". Eurasia Group now puts the chance of escalation at 65%, up from 35%, and wrote: "The conflict is likely to escalate."

The IEA agreed to release more than 20 million barrels of fuel, and the US offered up to 17 million barrels from its Strategic Petroleum Reserve.

On Monday, China reported third-quarter growth of 4.5%, above the 4.4% economists expected. Its trade surplus for the first nine months reached $938 billion. Inside China, fixed-asset investment fell 7.2% over the first nine months and property investment fell 20.6%, while retail sales grew 1.1% in September. China's National Bureau of Statistics wrote that "the problem of insufficient domestic demand remains prominent".