Former UN Assistant Secretary General Denis Halliday, a passenger on board the Rachel Corrie currently en route to Gaza, has petitioned President Obama to support the Irish-owned ship.

Halliday wants the president to stand behind Taoiseach Brian Cowen’s request that the ship not be interfered with by Israeli authorities.

He has asked those with Irish heritage in the United States to make sure they raise their voices about this issue.

"We also feel there is a role for the Irish diaspora here, in the US and elsewhere to lobby politicians over this continued illegal blockade of Gaza, which is causing such hardship to the Palestinian people,” Halliday told The Irish Times from the Rachel Corrie via satellite phone.

Halliday, who lives in Connemara, hopes that common sense can prevail and that the ship and those on it can deliver the cement and educational materials without incident.

“We are an unarmed, harmless, cozy, friendly group of Irish and Malaysians, including a Malaysian politician. Perhaps we can give Israel an opportunity to show that it does have some respect for human rights.”

The Rachel Corrie is due to arrive in Gaza on Saturday.

How the ship and those on it are treated will be closely watched all over the world after the widespread condemnation of the disproportionate use of force by Israeli commandos in a pre-dawn raid of humanitarian ships on Monday.

Rachel Corrie departing from Dundalk at the beginning of May