The Israeli government has warned that it could pull out of a United Nations probe into the clash on a Gaza-bound flotilla if IDF soldiers are called to testify. The panel is set to start investigations today.

Prime Minister Benjamin Netanyahu has said UN Secretary-General Ban Ki-moon had agreed that Israeli soldiers would not be questioned by the panel. Mr Moon has denied promising this.

A spokesman for Mr Netanyahu said: “Before Israel gave the green light to its participation we had discreet negotiations in order to ensure that this commission would not harm the vital interests of Israel.

"The prime minister said Israel would not co-operate with any commission that would ask to question soldiers".

After Israel agreed to co-operate with the investigation Mr Netanyahu said involvement was in Israel’s “national interest”.

An Israeli public investigation into the flotilla clash has already opened. Mr Netanyahu was first to testify and told the panel that Turkey ignored high-level warnings “intended to prevent a confrontation”.

Defence Minister Ehud Barak has also given evidence to the inquiry, headed by retired Supreme Court judge Jacob Turkel, with IDF Chief of Staff Gabi Ashkenazi expected to later this week.

Mr Barak said: "I carry overall responsibility for everything that took place in the systems under my command. I carry responsibility for the orders given on the political level.”

But he added: "The decision making process at the political level was not the reason for the reality that emerged at the end of the operation.”

He also said the flotilla was a "planned provocation".