Fallon was speaking on a visit to Cyprus from which Britain has been making its aid and surveillance flights over Iraq out of its sovereign air base at Akrotiri on the south coast.
Britain dropped more than a hundred tonnes of tents and water to Yazidi Kurds trapped in the Sinjar mountains of northwestern Iraq earlier this month by the advancing jihadists.
"We are continuing surveillance of northern Iraq so we can have a better picture of the humanitarian needs there," Fallon said, after talks with Cyprus President Nicos Anastasiades.
Britain deployed Tornado fighter jets to Akrotiri earlier this month for its Iraq surveillance flights.
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They have now been joined by the Royal Air Force's most modern surveillance aircraft, the Boeing RC-135 Rivet Joint, Fallon told Sky News earlier.
Fallon held talks with commanders at Akrotiri before heading to the meeting with Anastasiades at his residence in the hill resort of Troodos.