"The Government of Israel has stated its desire to avoid a confrontation and a repeat of Monday's tragic events on the Mavi Marmara. It remains a U.S. priority to provide assistance to the people of Gaza," National Security Council Spokesman Mike Hammer said in a White House statement.

"In the interest of the safety of all involved, and the safe transmission of assistance to the people of Gaza, we strongly encourage those on board the Rachel Corrie and other vessels to sail to Ashdod to deliver their materials to Gaza", Hammer said

Hammer said the U.S. is working with Israel, the Palestinians, and other partners to find new ways to deliver aid to Gaza, while preventing the importations of weapons.

He said the current arrangements are unsustainable and must be changed, calling on all parties to avoid any unnecessary confrontations and to ensure the safety of all involved.

On Monday, Israeli commandos raided the Gaza-bound aid flotilla, including Mavi Marmara, killing nine and injuring dozens. Its deadly attack has caused international outcry.

Israel is now preparing to intercept another aid ship, Rachel Corrie, which is expected to arrive in Gaza on Saturday, raising new fears that tensions may escalate.