Germany called for an independent inquiry into the killing of 42 loyalists of Egypt's ousted president Monday, saying it feared political violence in the country could continue to spiral.

Expressing "shock" about the reports of demonstrators killed while protesting last week's military coup in Cairo, the foreign ministry in Berlin said that all sides must now refrain from bloodshed.

German Foreign Minister Guido Westerwelle on Wednesday said the military intervention that toppled Islamist president Mohamed Morsi was "a major setback for democracy in Egypt" and called for "dialogue and political compromise.”

"This is a major setback for democracy in Egypt," Westerwelle told reporters during a visit to Athens. "It is urgent that Egypt return as quickly as possible to the constitutional order... there is a real danger that the democratic transition in Egypt will be seriously damaged."

German Foreign Minister Guido Westerwelle expressed grave concern Tuesday about Egypt's political crisis and urged all sides not to squander the hopes of the democratic revolution.

"I am deeply concerned and I do not want to hide it," he told reporters.

Germany stressed Tuesday that the fate of jailed Ukrainian opposition leader Yulia Tymoshenko would have a decisive impact on Kiev's ambitions for closer ties with the European Union.

Foreign Minister Guido Westerwelle told reporters after talks with his Ukrainian counterpart Leonid Kozhara that negotiations were ongoing to secure Ukrainian permission for the ailing Tymoshenko to receive medical treatment in Germany.

A German court Tuesday jailed a married couple for spying for the Russian secret services for more than 20 years in one of the country's biggest espionage cases since the Cold War.

The pair, identified only by the code names Andreas and Heidrun Anschlag, were planted in the former West Germany from 1988 by the Soviet Union's KGB and later worked for its successor the SVR, the court heard.

German Chancellor Angela Merkel may well have known about sweeping U.S. and British online surveillance activities, the chief of the opposition Social Democrats charged in an election-year attack on Monday.

"The chancellor's reaction raises the suspicion that she was aware of the spying ... at least in principle," Sigmar Gabriel wrote in a commentary for Tuesday's edition of the Frankfurter Allgemeine Zeitung daily.

Three members of German aid group Gruenhelme, reported missing for more than six weeks, have been kidnapped in northwest Syria, the organisation said.

"It has been 45 days since three members and employees of Gruenhelme were kidnapped overnight on May 14-15, in the village of Harem" in northwest Idlib province near the Turkish border, the group's founder Rupert Neudeck said in a statement dated Friday.

German Chancellor Angela Merkel on Thursday said she was glad Turkey could resume EU membership talks but stressed, after Ankara's crackdown on protesters, that for Europe human rights are "non-negotiable".

The European side "didn't pretend that nothing had happened" in its recent talks with Turkey, she said, referring to the tough response by Prime Minister Recep Tayyip Erdogan's government against the anti-government demonstrators.

German authorities staged raids Tuesday after uncovering an alleged Islamist plot to carry out bomb attacks using model airplanes, federal prosecutors said.

Elite police units stormed nine sites in southern and eastern Germany as well as Belgium based on suspicion of "preparation of grievous acts of anti-state violence" as well as money-laundering, the federal prosecutor's office in the southwestern city of Karlsruhe said in a statement.

After a three-year break, the European Union on Tuesday agreed to reopen EU membership talks with Turkey but delayed them several months due to concerns notably from Germany over Ankara's tough crackdown on anti-government protests.

Ireland, which holds the rotating EU presidency, said EU ministers agreed to resume entry talks with Turkey but that negotiations proper "will take place later this year."