Doubts have been cast on the credibility of the Union of Orthodox Hebrew Congregation’s latest attempt to deal with allegations of sex abuse against one of its senior rabbis.

Last Friday, the Union announced the names of three rabbis, two from Israel and one from the USA, to sit on a special beth din, which would examine complaints against Rabbi Chaim Halpern of the Divrei Chaim synagogue in Golders Green.

But already questions have begun to be asked about the tribunal — particularly the attendance of one member, Rabbi Naftoli Nussbaum of Jerusalem.

Federation Beth Din head, Dayan Yisroel Lichtenstein, said this week: “I am aware that he [Rabbi Nussbaum] never agreed to come to London.”

The other Israeli member, Rabbi Sariel Rosenberg, from Bnei Brak, confirmed that he would be flying to London for an “investigation”. However, asked about the timing, he said: “I don’t know when.” Neither Rabbi Nussbaum, nor the third rabbi, Avrohom Baruch Rosenberg of Monsey in upstate New York, were available for comment.

Sources who have heard some of the complaints against Rabbi Halpern have questioned whether any of the women involved would be willing to take part in the proposed Beth Din hearings.

One Golders Green rabbi who has previously denounced Rabbi Halpern said that the idea “carries no weight with us. The whole thing is a farce.”

The Union, which has so far not disclosed the venue or date of any hearings, declined to comment.

It is three months since a group of north-west London rabbis alerted Union head Rabbi Ephraim Padwa to complaints about marriage counselling sessions offered by Rabbi Halpern.

Last month, Rabbi Padwa moved to oust Divrei Chaim’s synagogue from the Union, only to allow it back in hours later. Rabbi Halpern has maintained his innocence, saying he has acted in accordance with Jewish law.

One congregation, North Hendon Adath Yisroel, has already quit the Union in protest at its handling of the Halpern affair.

Discussion has also been taking place among rabbis for a new strictly Orthodox alliance in north-west London.

There is also talk in the area of the imminent launch of a new kosher chicken supplier – which some believe could start to chip away at the income of the strictly Orthodox Kedassia, the kashrut operation that helps to fund the Union.