German Foreign Minister Guido Westerwelle said Berlin was "very worried by the recent dispute," and urged immediate dialogue by "all parties" to seek a solution.
UN chief Ban Ki-moon, senior European foreign ministers and officials in Washington all urged the one-time allies to end their increasingly poisonous dispute that they worried could impact on the wider Middle East.
"I sincerely hope that Israel and Turkey will improve their relationship," Ban told reporters in the Australian capital Canberra.
"Both countries are very important countries in the region and their improving relationship, normal relationship, will be very important in addressing all the situations in the Middle East, including the Middle East peace process."
The UN leader said he had been trying to help the countries improve their relationship since May 31, 2010 when Israeli troops boarded a Gaza aid flotilla, leading to the deaths of nine people including eight Turks.
Turkey pulled its ambassador out of Tel Aviv in the immediate aftermath of the raid, but on Friday Foreign Minister Ahmet Davutoglu announced that diplomatic ties would be further downgraded after a UN probe slammed the "excessive" force used in the raid, for which Israel has failed to apologise.
As well as announcing the Israeli ambassador Gaby Levy was being expelled, Davutoglu also said all bilateral military agreements were being suspended.
Davutoglu spent Saturday with his European Union counterparts, who sent a clear message they wanted an end to the spat.
"Our wishes are like those of the UN secretary general, who said that this dispute between Israel and Turkey must be resolved through dialogue and mutual understanding, not via other means," French Foreign Minister Alain Juppe told reporters at an informal meeting in the Polish Baltic Sea port of Sopot.
There were also similar calls to mend fences from Washington.
The United States "has longstanding friendships with both Israel and Turkey", said State Department spokeswoman Victoria Nuland, urging the two sides "to look for opportunities to improve their longstanding relationship".
Davutoglu himself refused all comment at the talks in Poland.
The Turkish measures came after a UN-mandated report criticised Israeli troops for using "excessive" and "unreasonable" force when boarding the ferry Mavi Marmara on May 31, 2010.
It added, however, that the flotilla "acted recklessly in attempting to breach the naval blockade," and the Israeli forces "faced significant, organised and violent resistance from a group of passengers".
The report's release was delayed several times because of the failure of Turkey and Israel to agree a final version. It was finally handed to Ban on Friday.