The US military is considering offering protection to foreign diplomats in Baghdad, the US ambassador has said.
Algeria confirmed its two diplomats were killed by their captors
Zalmay Khalilzad said diplomats must "have a sense of security" in Iraq, but admitted some may fear US help could make them greater targets.
Al-Qaeda in Iraq has said it was behind the killing of Egypt's top diplomat and two Algerian envoys this month.
Meanwhile, the US military says two of its soldiers have died in clashes with insurgents near the Syrian border.
Earlier, it said nine suspected militants had been killed in US air strikes on several buildings - believed to have been used as safe houses - in the town of Haditha.
Mr Khalilzad's comments to reporters came a day after Algeria confirmed its two abducted diplomats had been killed by their captors.
The al-Qaeda-linked group, thought to be led by Jordanian-born militant Abu Musab al-Zarqawi, claimed responsibility for killing top envoy Ali Balarousi and colleague Azzedin Belkadi.
Zalmay Khalilzad wants foreign diplomats to remain in Iraq
The group also claimed responsibility for the killing of Egypt's new ambassador to Iraq, Ihab al-Sherif, a few days earlier.
"Coalition forces... are planning to look at this problem and see what could be done to fix the security for the diplomats," Mr Khalilzad was quoted by the Associated Press as saying.
"It's very important for foreign diplomats who come here to have a sense of security."
He acknowledged that some Arab diplomats may fear becoming targets of even greater attacks if they agree to a US military presence around their mission buildings.
"We have not accepted taking on the mission at this point," he said.
"But what we've agreed is, we will look at this, see what the problem is, and what the options might be for assisting."