The euro zone's biggest economies prepared to unveil plans to spend tens of billions of euros in state funds to prop up their banking systems, the Wall Street Journal reports Monday. The plans included partial nationalization of banks and provision of state-guaranteed loans, according to the Journal. The euro-zone leaders also agreed to loosen mark-to-market rules. A decision on how to implement the plans might be made as early as this week, the newspaper reports. French President Nicolas Sarkozy said Germany, France and Italy would detail their national plans at about the same time on Monday. France will indicate the amount of bank loans it is willing to guarantee. Sarkozy also said France will pass a bill in the coming days creating a special-purpose state vehicle that will raise enough money to nationalize any distressed bank. Germany's plan, according to people familiar with it, could include massive government guarantees for banks' debts and capital injections for some banks, the Journal reports. Meanwhile, the U.K. government is expected to unveil Monday a plan that could hand it control of two large banks, Royal Bank of Scotland ( RBS) and HBOS, the Journal reports.