European stocks declined the most in more than three weeks as Standard & Poor’s said Greece may have to restructure its debt again.

European governments are preparing for a one-year increase in the ceiling on rescue aid to 940 billion euros ($1.25 trillion) to keep the debt crisis at bay, according to a draft statement written for finance ministers before they meet in Copenhagen tomorrow. German Chancellor Angela Merkel this week gave her first indication that she is prepared to allow an increase in the firewall.

An indicator of economic confidence in the euro region unexpectedly declined in March. An index of executive and consumer sentiment in the 17-nation euro area dropped to 94.4 from a revised 94.5 in February, the European Commission said.

National benchmark indexes fell in all of the 18 western European markets, except Iceland. The U.K.’s FTSE 100 slipped 1.2 percent, while France’s CAC 40 Index declined 1.4 percent and Germany’s DAX slumped 1.8 percent.

H&M dropped 4.9 percent to 238.1 kronor in Stockholm, the largest decline since September, after reporting first-quarter profit that missed analysts’ estimates as textile costs and markdowns weighed on profitability.

Roche Holding AG, the biggest maker of cancer drugs, fell 1.8 percent to 157 francs after raising its hostile takeover offer for Illumina Inc. by 15 percent to about $6.7 billion.

International Power Plc rallied 5.6 percent to 405 pence as it received an indicative offer from GDF Suez SA of 6 billion pounds ($9.5 billion) for the 30 percent stake it doesn’t already own.