After simmering for months, a crisis between Israel and Germany has erupted into the open, putting serious strain on a special relationship painstakingly built up after the Holocaust.
First, Chancellor Angela Merkel in February postponed an annual government meeting with Israel, then this week, Israeli Prime Minister Benjamin Netanyahu refused to meet Germany's foreign minister in Jerusalem.
What was once "unthinkable" has become real -- the gild on the ties between Germany and Israel may be fading.
Due to its historical responsibility as the perpetrator of the Holocaust that killed six million Jews, Germany has not only been Israel's staunch ally but has also shied away from openly criticising the Jewish state.
But Netanyahu -- Israel's most right-wing leader to date -- has irked Berlin by pressing on with settlement building in the Palestinian territories despite repeated warnings from world powers that it would harm any prospects of peace.
On Tuesday, the tensions ratcheted up a notch with Netanyahu scrapping at the last minute a planned meeting with Sigmar Gabriel because the German foreign minister refused to cancel talks with Israeli rights groups.
Gabriel sought to minimise the damage, saying it was "not a catastrophe".
But he also stressed he wanted "to say openly that I think we should not become the pawn of Israel's domestic politics."
Merkel threw her support behind Gabriel, calling Netanyahu's decision "regrettable".
"It should not be problematic for foreign visitors to meet with critical representatives of civil society," her spokesman Steffen Seibert told reporters.
German public opinion was also largely on the foreign minister's side, with the Spiegel weekly saying that "Netanyahu's government has pushed the historically imperative special treatment to its limits".
"Certainly, Israel can never be just another country for Germany. Special consideration for the past is required, and, until today, also special diplomatic sensitivity," it said.
"But historical guilt cannot lead Germany to accept an Israeli government moving away from certain values that we have always shared."
- 'Treated as a joke' -
Berlin has been troubled for months by Israel's settlement building programme and attempts to crack down on critical NGOs.
Rather than air its unhappiness in the open, Merkel's government had sought previously to express concerns behind the scenes.
Right after the Knesset approved a new law legalising dozens of Jewish settler outposts in the occupied West Bank, the German foreign ministry openly voiced doubts for the first time in January about whether Netanyahu intended to respect his pledge for a two-state solution.
A month later, Merkel's government cancelled an annual consultation with Israel which had been planned for May in Jerusalem.
Ostensibly, the reason was a diary problem. But the message was clear.
"Merkel has now changed her tone because the Israeli government has taken the reservations expressed by Germany as a joke," said Moshe Zimmermann, a geopolitical analyst at the Hebrew University of Jerusalem.
- 'Serious differences' -
In the immediate aftermath of World War II, the young Jewish state had boycotted then West Germany, until a deal in 1952 offering reparations to Israel.
Both sides -- and subsequently a reunified Germany -- have since built up a close relationship.
In a sign of their special ties, the two governments met annually for bilateral talks.
And Merkel has repeatedly said that "the security and right of the state of Israel to exist is a fundamental tenet for Germany".
Their security and economic relations are healthy, borne out most recently by the signing of a military deal for Israel's purchase of three German submarines -- with a substantial discount of one-third of the price.
But politically, the differences between the allies are widening.
Norbert Roettgen, who heads the German parliament's foreign affairs committee, said it plainly: "The differences are serious, everyone who holds Israel close to their hearts can not help but be sad and depressed by this blockade of (peace talks)."
For analyst Eldad Beck, an Israeli journalist and writer of the book "Merkel, Israel and the Jews", the friction may have also arisen as Germany has begun moving away from treating Israel with kid gloves.
"Over the last 20 years, Germany has been normalising its relationship with Israel. 'Normalising' often has a positive connotation, but here it's the reverse, it's about ending a unique status accorded to the relationship with Israel."