Washington: Retired General John Allen, President Barack Obama`s special envoy to the coalition fighting Islamic State, said on Thursday the U.S.-led effort is weakening the militant group.
"We`re clearly degrading its capabilities," Allen told a U.S. House of Representatives Foreign Affairs Committee hearing on Obama`s Middle East strategy.
"The allure of the so-called caliphate is under direct assault," Allen said.
Islamic State had lost more than a quarter of the populated territories it had held in Iraq, he said, but added that the situation in Syria is more complex.
Several lawmakers questioned Allen closely about U.S. involvement in strikes in the Iraqi city of Tikrit, where Islamic State militants have been holding out for more than three weeks.
The operation puts the U.S. coalition on the same side of that fight as an Iranian-backed militia, worrying lawmakers.
"It is hard to see how empowering Iran`s proxies in the short-, medium-, or long-term interest of an inclusive Iraq or a stable Middle East," said U.S. Representative Ed Royce, the committee`s chairman.
Allen declined to disclose details about the operation, but said the United States was providing information and intelligence.