The bitter row between Turkey and Europe in the referendum campaign on expanding President Recep Tayyip Erdogan's powers risks causing lasting damage to their often fraught relationship, analysts say.
Once the current spate of votes in Turkey and Europe is over, the dispute will leave both sides at a historic crossroads to decide on the nature of their future alliance.
Turkey is a key member of NATO and has sought to join the European Union as a strategic goal in an agonisingly long process dating back to the 1960s.
There have been numerous rows over the last few years -- especially over human rights -- but none have matched the volcanic acrimony of the current clash as Turkey gears up for the April 16 plebiscite.
Erdogan has said the Netherlands and Germany were acting like the Nazis for preventing his ministers from holding rallies abroad to push for a 'yes' vote in the referendum, leaving The Hague and Berlin aghast.
"Such tensions leave their mark and weaken the perception that Turkey and Europe share a common fate," Ilter Turan, professor of political science at Istanbul's Bilgi University, told AFP.
- 'Post-poll normalisation?' -
The crisis has come about as Erdogan -- who survived a military coup bid in July -- seeks to tip the balance in a tight referendum campaign and to strike a chord with nationalist voters.
Dutch Prime Minister Mark Rutte is meanwhile conscious of the need to take a hard line against Erdogan as he shapes up to face the ultra-right populist Geert Wilders in Wednesday's highly-watched election.
German Chancellor Angela Merkel is facing an election in September, while France meanwhile votes in a two-round presidential poll in April and May with Marine Le Pen of the far-right National Front a serious contender.
Analysts say that once the excesses of the election frenzy are calmed, there will again be a chance to put pragmatism before sensationalism.
Turkey, whose economy has weakened over the last few months from the stellar heights seen in the early years of Erdogan's rule, will not want to lose the EU as its key trade partner.
Turan predicted that once the rhetoric of the elections is over "both sides will work to normalise their relations".
"Turkey and the EU have so far not wanted to cut their relations -- even though they were not keen to improve them," he said.
- 'Little chance' -
Yet the breakdown in civility in the current dispute has raised doubts over the future viability of the membership bid, which some analysts have already argued should be replaced by a more realistic partnership agreement.
In public speeches ahead of the referendum, Erdogan has repeatedly raised the spectre of bringing back capital punishment, a move that would automatically end Turkey's attempt to join the bloc.
Meanwhile, Ankara has moved sharply to rebuild its relationship with Moscow -- damaged after a 2015 shooting down of a Russian plane -- with Erdogan saying last week ties were now normalised.
Erdogan's influential spokesman Ibrahim Kalin wrote in a newspaper column Tuesday entitled "Turkey, Europe and a narrowing horizon" that the acts of the Dutch government showed the emergence of a "hypocrisy" on the entire continent.
"Despite the reality that all sides would benefit from effective relations between the EU and Turkey, there is little chance that the crucial relationship improves in the near term," analysts at the Soufan Group said in a research note.
- 'Bridges burned' -
Turkish officials argue that the majority Muslim country's economic prosperity and rising power under Erdogan have not been welcomed by Europe and the country is prepared to go its own way to develop.
"Turkey's growth is a hope for some and has become a nightmare for others -- like Holland and Germany," said Erdogan, who has made much to deepen links with Africa and South America over the last year, as well as Britain as it heads for Brexit.
Marc Pierini, a former EU ambassador to Turkey and visiting scholar at Carnegie Europe, said in the short term there was "no way out" of the crisis as Erdogan would do everything to win nationalist votes in the referendum campaign.
"In the medium-term, one can hope that the fever will subside," he told AFP.
"Yet bridges have been burned at personal level -- using a 'Nazi' narrative is the most extreme vexation one can possibly use in EU politics," he said.