Israel has expanded the mandate of a commission investigating a deadly raid on a Gaza-bound aid flotilla, enabling the panel to compel witnesses to appear and testify under oath.
However, the decision by Israel's cabinet on Sunday does not widen its remit to include examination of political leaders' decision-making in ordering the May 31 raid in which nine Turkish activists were killed.
"The government has unanimously decided to extend the powers of the Tirkel Commission. The commission of enquiry will be joined by two experts and will hear witnesses speaking under oath," an official statement said.
The five-man inquiry panel led by former Supreme Court Justice Jacob Tirkel will now have subpoena powers and witnesses will be sworn in, effectively exposing them to perjury charges for any false testimony.
Tirkel has said he would summon Binyamin Netanyahu, the prime minister, Ehud Barak, the defence minister, and Lieutenant-General Gabi Ashkenazi, Israel's military chief, to appear.
Netanyahu has said he, Barak and Ashkenazi would testify.
Other military personnel are not likely to appear before the panel but will be questioned in a separate military investigation.
Amid an international outcry over the raid, Israel rejected a proposal by UN Secretary-General Ban Ki-moon for an international inquiry, but appointed two foreign observers - David Trimble, a Northern Ireland politician and Nobel Peace Prize laureate, and Canadian jurist Ken Watkin - to the panel.
Tirkel has said the commission's mandate calls for an examination of whether Israel's naval blockade of the Hamas-controlled Gaza Strip and the flotilla's interception conformed with international law.
It also will investigate the actions of the convoy's organisers and participants.
Israel has said its commandos were enforcing a blockade necessary to prevent weapons from reaching Hamas fighters in the Gaza Strip and that they only opened fire when activists with knives and clubs assaulted a boarding party.
In response to Western criticism, including from its biggest ally, the United States, Israel has since eased the land blockade of Gaza, allowing most civilian goods through, while continuing to enforce the naval embargo of the coastal territory.