JNF UK is challenging the planned transfer to the Israeli government of lands bought with money raised by diaspora Jews.

Samuel Hayek, chairman of the charity, described the arrangement, which is part of a land reform currently being hotly debated in the Knesset, as an “issue of concern”.

The controversy has arisen over the Israeli government’s wish to enable householders to own the freehold of their properties, rather than leasehold as at present.

Mr Hayek explained that the reform would cover a “substantial amount of land” in central Israel which is currently owned by Keren Kayemeth Le’Israel (KKL), JNF UK’s partner.

The government therefore struck a deal with the KKL to transfer those portions of land to the state.

In return, the state would transfer state lands in the Negev for development to KKL, preserving KKL’s current holding of around 13 per cent of the land in Israel.

But Mr Hayek believes the proposed swap requires more discussion with JNF groups over the world, which historically raised funds for KKL to buy land in Israel.

“KKL holds the land in trust for the Jewish people,” he explained. “My position is that KKL should have a consultation with the various representatives of the Jewish people on this issue before it makes a fundamental decision.”

A conference of JNF groups due to have been held in London in summer has been postponed because too few participants were able to attend at the time. But Mr Hayek hoped to rearrange it for September. “We want to go ahead because this is a major issue for the Jewish people,” he said.

A spokesperson for KKL, however, maintained that the agreement between the state and KKL had been already approved “by the management of the KKL including representatives from all KKL-JNF groups. The agreement was also ratified by the KKL board of directors.”

The arrangement was intended to “protect” KKL from the loss of ownership through the land reform, she explained.

“In the framework of this agreement, KKL will transfer to the state of Israel urban land used for construction, mainly in the centre of the country, and in return KKL will receive vacant land in the Negev and the Galilee.

“KKL will retain the number of dunams under its ownership and can continue with the Zionist enterprise of developing the Negev and the Galilee.”

She added that the government could implement the reform without the agreement of KKL, because KKL only has a minority of representatives on the council of the Israel Lands Administration.

This is the body which administers public land, including that owned by both the state and KKL.