German opposition blasts Merkel over U.S. spying scandal BERLIN, July 16 (Xinhua) -- The German opposition parties have been criticizing Chancellor Angela Merkel's coalition government over its handling of the United States' massive surveillance program in Germany, as the public outrage shows no signs of abating with the looming general elections in September. Social Democratic Party (SPD) Chancellory candidate Peer Steinbrueck said in the Tagesspiegel newspaper that Merkel broke her oath of office as she had failed to prevent damage to the German people from the "threats of economic and political espionage." He has also called for a parliamentary inquiry. He criticized what he called Merkel's vague comments on the spying issue and her claim to have only been made aware of the U.S. spying programs through media reports. The opposition also attacked Interior Minister Hans-Peter Friedrich, who returned to Germany last weekend after meeting in Washington with U.S. Attorney General Eric Holder and Vice President Joe Biden, saying that he was satisfied with the meetings and the U.S. National Security Agency's Prism program have prevented terrorist attacks. Steinbrueck said Friedrich had been deceived during the hasty trip to Washington and it "has less to do with friendship than with obedience." He demanded a full explanation of German co-operation with the U.S. secret service. Joining SPD's criticism, the Green Party's lead candidate Juergen Trittin told local media that Friedrich had "failed plain and simple." Trittin defended Germany's economic interests, saying that the economy cannot be spied upon and intellectual property must be protected, proposing that "full range of cooperation with the Americans be examined." A recent report by Der Spiegel, citing classified documents disclosed by fugitive whistleblower Edward Snowden, said Washington was monitoring phone calls and Internet data connections in Germany as well as spying on the headquarters of the European Union and its offices in Washington and the United Nations in New York. Approaching the surveillance issue with caution, Merkel said in a TV interview at the weekend that she expected the U.S. government to stick to German law in the future, pledging that Berlin will take a "very strict position" in talks on EU-wide data rules. She also called for an EU regulation on telephone and Internet data protection requiring internet companies to disclose to whom they transfer data as well as an international treaty to ensure privacy protection. Nevertheless, Merkel has earlier defended German intelligence service and intelligence cooperation with other countries, saying that the intelligence work is essential for the security of citizens. German observers and media do not see much chance that the opposition could gain leverage from the U.S. spying issue in their final fight during the election campaign before the Sept. 22 election. Der Spiegel commented that Steinbrueck's aggressiveness in the spying scandal is not without risk as "many will interpret loud attacks from a candidate who is behind as an act of desperation." A fresh opinion poll by public broadcaster ZDF showed that 62 percent of respondents still support Merkel as the preferred chancellor. It also gave Merkel's Christian Democratic Union (CDU) a 41-percent support and its junior coalition partner the Free Democrats 5 percent, giving the coalition a comfortable lead over the combined support for the SPD and Greens, with 26 percent and 13 percent respectively.