United Synagogues have been warned by the US not to confuse a Kol Nidre Appeal card sent out by UJIA with its own appeal at Yom Kippur.
The US has decided to run a stand-alone appeal for the first time this year, no longer guaranteeing 40 per cent of the Kol Nidre take to UJIA.
Some US synagogue members were puzzled to receive pledge cards in the post from UJIA titled "The Kol Nidre Appeal".
US consultant marketing director Ian Myers has written to rabbis and synagogue representatives advising: "Your community should be aware that this appeal from UJIA is not the same as that running in your shul and that the recipients are different."
The UJIA appeal had been "presented in a way that makes it likely that there will be confusion with the appeal due to run in a couple of weeks in your shul".
One-third of the US appeal will go to chaplaincy and its young people's division, Tribe.
Local synagogues will be free to allocate the remaining two-thirds, with a recommendation that at least 25 per cent goes to Israel.
UJIA chief executive Douglas Krikler said it would not have taken the action "had not the United Synagogue unilaterally changed the whole nature of the Kol Nidre Appeal".
The charity had sent cards only to members of US synagogues who had previously contributed to UJIA and whose synagogue had decided no longer to include the UJIA as a beneficiary of the Kol Nidre Appeal.
But "most of the key" US congregations had chosen to continue contributing to the UJIA campaign, so UJIA had not written to their members.
Mr Krikler added that UJIA had previously gone along with changes made by the US, including taking over the administration of the Kol Nidre Appeal and then reducing the allocation to UJIA.
But this year's move by the US had "radically undermined the fabric of the appeal".
UJIA would face "a potential shortfall of several hundred thousand pounds" if it did not run its own appeal.