(VOVworld) – The US-led air strike campaign targeting the self-proclaimed Islamic State (IS) is on the right track and has achieved success in its early days, said White House press secretary Josh Earnest.

White House press secretary Josh Earnest

With the IS about to seize 2 key areas in Iraq and Syria. Earnest told reporters at a Wednesday press conference that the strategy of air strikes against the IS was having a strong effect:“We are in the early days of executing this strategy, but certainly the early evidence indicates that this strategy is succeeding. The use of military force has succeeded and has pushed back the IS advances, stopping the siege of vulnerable humanitarian target, the ability of IS to command and control forces in Syria. At the same time, I don’t think the air strike can dramatically reverse the situation over night. We’re aware about the fact that this is a longer term proposition. ”

Earnest’s announcement was made while US President Barack Obama and Defense Ministers of countries in the US-led coalition were discussing ways to ensure the campaign’s effectiveness.  Several military leaders said air strikes are not enough in the fight against the IS.

Smoke rises after an U.S.-led air strike in the Syrian town of Kobani on Octotber 10

The US forces conducted 21 air strikes focused on halting IS advances against Kobani, Syria, on Tuesday. The air strike was the largest scale attack since the US campaign began. Current air strikes are aimed at preventing aid to IS and IS’s operations in Kurdish-controlled regions.

Earnest said the air strikes in Iraq and Syria have cost 424 million USD since its beginning on August 8 inside Iraq.