The religious leader of London’s Union of Orthodox Hebrew Congregations moved this week to prevent the creation of an eruv in his own back yard.

Rabbi Ephraim Padwa, head of the Union’s rabbinate, urged members of the strictly Orthodox community not to back plans for a local eruv that would cover the Charedi strongholds of Stamford Hill and Stoke Newington in North London.

The Union has long opposed the use of the five-year-old North-West London eruv, which serves Hampstead Garden Suburb, Hendon and Golders Green, arguing that its boundaries fail to meet the requirements of Jewish law.

But now a group of activists are trying to draw up plans for a similar facility for the 20,000-plus Charedi community in Hackney and Haringey.

Shabbat rules normally prohibit the carrying of items in public, but within the boundaries of an eruv, it is permissible to carry certain objects for Shabbat use or push wheelchairs and prams.

In a handwritten letter in Hebrew, Rabbi Padwa was adamant: “Nobody should get involved with establishing an eruv here in our town.”

One local businessman who was believed to be a supporter of the project is understood to have pulled out after Rabbi Padwa’s intervention.

A map of the proposed eruv area has been circulating in Stamford Hill.

But one rabbi said to be in favour of the plan was unavailable for comment, according to a woman who answered the phone at his home.

The technicalities of constructing an eruv are among the most complex in Jewish law and rabbis differ over their application.

Where there are no natural boundary lines such as a river or railway, symbolic gateways — consisting of poles linked with thin wire — may be used to mark parts of the eruv perimeter.

Opponents of the North-West London eruv, for example, argue that it is invalid because it incorporates an unbounded thoroughfare, which serves a town with more than 600,000 residents — the North Circular Road.

But supporters of the eruv argue that the 600,000 figure applies to daily users of the road and that the North Circular carries fewer travellers.

Last month, a group of Orthodox businessmen sponsored the distribution of a glossy brochure to thousands of homes in Golders Green and Hendon, quoting leading rabbinic authorities in support of the North-West London eruv, which is under the supervision of the London Beth Din.

Eruvs are rapidly growing in popularity. Edgware’s has been operational for a year and a half, Borehamwood and Elstree’s is due to come on stream and the United Synagogue is believed to have more than half-a-dozen other proposals under consideration.