Stocks in emerging markets fell the most in a month yesterday as Russia’s threat to invade Ukraine spurred the worst sell-off in the Micex index since 2008.

Russia’s benchmark plunged as much as 11 percent and the rouble depreciated 1.7 percent against the dollar. All but two developing-nation equity gauges dropped, with stocks in Poland, Romania and Hungary decreasing more than 2.5 percent. The Kospi index slid the most in a month in Seoul after North Korea fired two missiles and data showed South Korean exports missed estimates.

The MSCI emerging markets index lost 1.4 percent to 952.74 by 11.22am in London.

The Micex index sank for a fifth day, headed for the steepest decrease since November 2008, while the UX index slumped 9.4 percent in Kiev, the most since June 2012.

A Bloomberg gauge tracking developing nation currencies retreated 0.3 percent.

Mechel, Russia’s biggest coking coal producer, plunged 22 percent to a record low in Moscow, while Gazprom, which pumps gas through Ukraine, slumped 13 percent.

Russia unexpectedly raised its key interest rate by 150 basis points, Bank Rossii said on its website. It had been left unchanged since August 2012.

The rouble weakened 1.8 percent against the central bank’s target basket of dollars and euros to a record low.

All 10 industry groups in the developing nation measure fell yesterday, paced by energy companies, which slid 3.7 percent. – Bloomberg