The driver of an excavator was killed and eight other people injured when a World War II-era bomb blew up during earthworks in Germany on Friday, police said.

The blast wave from the sleeper bomb blew out the windows of surrounding buildings and could be felt for several kilometers (miles), said police and residents.

Unknown attackers fired shots at the German ambassador's residence in northern Athens early on Monday but caused no injuries, police sources said.

The attack happened around 3:30 am (0130 GMT) and the assailants are thought to have fled by motorbike.

Russia's supreme court on Wednesday agreed to review the two sets of convictions against Kremlin critic Mikhail Khodorkovsky following his surprise early release from prison and lightning transfer to Germany.

Russia's former richest man was pardoned by President Vladimir Putin last week just eight months before his scheduled release after more than a decade behind bars.

Germany's first female defense minister visited troops in Afghanistan on Sunday and appealed for President Hamid Karzai to sign a troubled deal to allow some foreign forces to stay in the country after 2014.

Ursula von der Leyen, who was appointed a week ago, made an unannounced two-day trip to the northern city of Mazar-i-Sharif to meet German soldiers in the NATO coalition that is now withdrawing from Afghanistan.

The freed Russian ex-tycoon Mikhail Khodorkovsky is likely to stay out of politics but may write about Russia in the same way as the celebrated dissident Soviet author Alexander Solzhenitsyn, a German analyst who helped in his transfer said on Saturday.

Political analyst Alexander Rahr, the author of several books on Russia, told the RTVi channel in an interview that Khodorkovsky's dramatic release Friday had been the result of "clandestine diplomacy" between Russia and Germany.

German Chancellor Angela Merkel hailed Friday a role played "behind the scenes" by former German foreign minister Hans-Dietrich Genscher in helping to secure the release of Kremlin critic and Russian ex-oil tycoon Mikhail Khodorkovsky.

"The German government appreciates the efforts of former federal minister Genscher who worked intensively on the case behind the scenes," Merkel's spokesman Steffen Seibert said in a statement.

With Iraqi President Jalal Talabani in Germany for treatment, the country has been without a key mediator during a disastrous year of political conflict and surging violence.

Talabani, a veteran Kurdish leader who is now 80, left Iraq for treatment on December 20 last year after suffering a stroke two days before, and has yet to return.

German Chancellor Angela Merkel said Wednesday that European Union members must be ready for treaty changes to strengthen the 28-member bloc, speaking on the eve of an EU summit.

"Since the Lisbon Treaty we have a situation in Europe where everyone says, 'we can develop everything but we can't change the treaties'", Merkel told parliament.

Germany and Britain are providing logistical support to a military force in the Central African Republic, a French minister said Wednesday, amending comments made earlier indicating they were considering sending troops.

Speaking on RTL radio earlier Wednesday, European Affairs Minister Thierry Repentin said that Belgium could send troops at the end of January to prop up a 1,600-strong French force attempting to quell deadly sectarian violence in Central Africa.

As German Chancellor Angela Merkel started a third term Tuesday, her conservative party also forged a landmark new alliance at the state level with the Greens party.

In the first such coalition to rule a large German state, Merkel's Christian Democrats (CDU) in central Hesse which includes the financial capital Frankfurt, agreed to launch a joint government with the environmentalist party.