US Secretary of State John Kerry said he was "extremely encouraged" by pledges of military assistance against Islamic State fighters by countries inside and outside the Middle East and that some nations had offered ground troops.

Kerry has been touring the Middle East to try to secure backing for US efforts to build a coalition to fight the armed group who have grabbed territory in Syria and Iraq.

"We have countries in this region, countries outside of this region, in addition to the United States, all of whom are prepared to engage in military assistance, in actual strikes if that is what it requires. And we also have a growing number of people who are prepared to do all the other things," Kerry said in remarks aired on Sunday on the CBS program "Face the Nation".

Kerry reiterated President Barack Obama's statement that US ground troops would not be used against the Islamic State.

"We're not looking to put troops on the ground," Kerry said.

"There are some who have offered to do so, but we are not looking for that at this moment anyway," Kerry said. He did not identify the countries.

On Thursday, Kerry won the backing for a "coordinated military campaign" from 10 Arab countries - Egypt, Iraq, Jordan, Lebanon and the six Gulf states.

"This is a strategy coming together as the coalition comes together and the countries declare what they are prepared to

do," Kerry said in the interview, taped on Saturday in Egypt.

"I've been extremely encouraged to hear from all of the people that I've been meeting with about their readiness and

willingness and to participate," Kerry added.

McDonough also said US President Barack Obama would meet on Tuesday with General John Allen, his newly appointed special presidential envoy for building the coalition against Islamic State.