Obama Offers US Help after Istanbul Attacks

President Barack Obama on Wednesday offered US security assistance to Turkey after 41 people were killed in a suicide assault on Istanbul airport, the latest in a string of attacks to rock the US ally.

Obama telephoned President Recep Tayyip Erdogan "to express his deep condolences on behalf of the American people," White House spokesman Josh Earnest told reporters traveling with the US leader to a summit in Ottawa.

"In the context of that call, he will offer any support that the Turks can benefit from as they conduct this investigation and take steps to further strengthen the security situation in their country."

"Any information that we obtain that could be useful to the Turkish investigation, we will certainly share that information," he added.

Earnest did not indicate whether Turkey had officially sought US assistance following the latest attack.

The United States earlier condemned as "heinous" Tuesday's bombing and gun assault on Istanbul's Ataturk Airport and pledged steadfast support for its NATO ally.

The assault, which comes at the start of Turkey's crucial tourist season, was the latest in a wave of attacks in Istanbul and the capital Ankara blamed it on Islamic State (IS) jihadists or Kurdish rebels.

Earnest, like Turkey, pointed the finger of blame at IS for the newest atrocity.

"We've made important progress in Iraq and in Syria against ISIL," he said using an alternate acronym for the group.

"But we continue to be concerned by the ability that ISIL has to carry out these kind of terrorist attacks, not just in Iraq and Syria but in other places."

Earnest said Obama would have a chance to meet with Erdogan "in some setting" when he travels to Warsaw for the upcoming NATO summit on July 8-9.

He said the attacks were certain to be raised Wednesday in Ottawa, where Obama joins Canadian Prime Minister Justin Trudeau and Mexican President Enrique Pena Nieto for a so-called "Three Amigos" summit.

"This is something that will certainly be on the minds of all three North American leaders," Earnest said.