European stocks plunged the most in three months as concern grew that Greece will default and more Spanish regions will follow Valencia in seeking a bailout.

BNP Paribas SA (BNP) and HSBC Holdings Plc contributed the most to a selloff by a gauge of bank shares. BHP Billiton Ltd. (BHP), the world’s largest mining company, retreated 2.8 percent as a policy maker in China warned of slowing growth. Groupe Eurotunnel SA slumped 5.8 percent after earnings missed analysts’ estimates. Royal Philips Electronics NV, the biggest lighting company, advanced 5 percent as profit increased.

The Stoxx Europe 600 Index (SXXP) tumbled 2.5 percent to 251.75 the close of trading, the biggest retreat since April 10.

National benchmark indexes fell in all of the 18 western European markets.

FTSE 100 5,533.87 -117.90 -2.09%, CAC 40 3,101.53 -92.36 -2.89%, DAX 6,419.33 -210.69 -3.18%

Spanish and Italian lenders reversed their losses after regulators imposed bans on short selling. Banco Santander SA (SAN), Spain’s biggest bank, rose 1 percent to 4.23 euros, erasing a 5.1 percent decline. Bankia SA (BKIA) advanced 7.6 percent to 66.5 euro cents after earlier dropping as much as 9.6 percent. UniCredit SpA (UCG) closed 0.2 percent lower at 2.43 euros, after tumbling as much as 7.5 percent.

Italy’s market regulator, Consob, introduced a week-long ban on short selling shares of some banking and insurance companies because of the “recent performance of stock markets.” Spain banned short-selling of all shares for three months.

Eurotunnel (GET) plunged 5.8 percent to 5.92 euros, the largest decline in 10 months. The company that operates the rail tunnels beneath the English Channel reported first-half earnings before interest, taxes, depreciation and amortization of 205 million euros. That missed the average analyst estimate of 224 million euros in a Bloomberg survey.

Wereldhave NV (WHA) plummeted 13 percent to 45.58 euros, the largest drop since at least 1989. The Dutch real estate company abandoned its dividend targets for this year and next as Chief Executive Officer Hans Pars quit.

Philips climbed 5 percent to 17.03 euros, the biggest gain this year. The company reported an increase in second-quarter profit as Chief Executive Officer Frans van Houten extended a savings program into a second year.