Jewish settler groups are digging an extensive tunnel network under Muslim areas of Jerusalem's Old City while building a ring of settlements around it to bolster their claim to the disputed city in any future peace deal, anti-settlement campaigners have told The Times.

One group, the Israeli Committee Against House Demolitions, said that settler tunnels could one day extend under the al-Aqsa mosque, Islam's third-holiest site, and claimed that extremists could use the access route to attack the structure in an attempt to prevent the creation of a Palestinian state. Settler groups flatly deny such allegations.

The tunnels are largely based on historical water wells or buried pilgrim routes, stretching from the Pool of Siloam in the Palestinian district of Silwan, where Jesus Christ is said to have cured a blind man, to the south and joining up with the Western Wall, the Jewish holy site.

Daniel Seidemann, an Israeli lawyer and member of the anti-settlement group Ir Amin, believes that the underground system will then extend from the Western Wall tunnel, which is already open, via settler-owned properties in the Muslim quarter and eventually link up with an ancient quarry, run by a right-wing Jewish group and known as Solomon's Stables, on the north side of the Old City, near the Damascus gate.

“The settlers are very interested in connecting the dots,” he said. “The intention is clear, to be able to enter the old city from the northern wall near the Damascus Gate, traverse the Old City without encountering a single Palestinian, emerge at the Western Wall, saunter across the plaza, re-enter the burrow and exit at Silwan.”

Jewish settlers have managed to lay claim to large tracts of the West Bank by building towns that are, under international law, illegal, establishing what they call “facts on the ground”. Now, it is claimed, they are trying to establish facts under the ground as well.

Ir Amin compares the illegal tunnelling under Palestinian homes to the excavations of the Western Wall, or Hasmonean, tunnel in 1996, which was so close to the Muslim holy sites that it triggered riots, the first big conflict to rock the Oslo peace process

Meir Margalit, field co-ordinator for the anti-demolitions committee, said that many excavations were only nominally under the control of the Israeli Antiquities Authority, which farmed out digs to private, well-funded Jewish organisations such as the extreme-right-wing group Elad, which controls the Silwan works. It also runs archaeological sites such as the City of David in Silwan, for which it claims entrance fees paid by visitors.

Mr Margalit said that the aim was not only to connect the tunnels, but to form a ring of Jewish communities around the old city, from Silwan and the Mount of Olives in the south to the Sheikh Jarrah in the north, to complicate any future peace deal. He also claimed that messianic extremists could use the tunnels to attack the al-Aqsa mosque, built on the stone plaza of an ancient Jewish temple destroyed by the Romans 2,000 years ago.

“Our main concern is that as the extreme Right feel existentially threatened as to any real potential for withdrawal from the occupied Palestinian territories, they may try to prevent it by committing a cataclysmic act that would change the course of history,” he said, citing the 1995 assassination of Yitzhak Rabin, the Prime Minister, by an Israeli extremist because of his commitment to the Oslo peace deal.

Aaron Horowitz, a member of Elad, denied that any tunnel went under the al-Aqsa mosque. He did say that the passages would eventually connect with the Western Wall and be open to tourists. “The tunnel goes back 2,000 years, to Herodean times. The ancient road was the way of the pilgrims,” he said. “I don't know that there are tunnels being dug under residential areas.”

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