EU leaders have approved a 12th package of sanctions on Russia over its invasion of Ukraine, a spokeswoman for European Council President Charles Michel said on the sidelines of a summit in Brussels. The package announced on Thursday provides for the introduction of an import ban on diamonds and the tightening of the price cap on Russian oil exports to third countries, which has so far had little effect. Trade restrictions are also planned for other goods as well as punitive measures against individuals and organizations supporting the Russian war against Ukraine. The agreement is to be formal…