Washington ? The Obama administration has concluded the risk of a security collapse in Iraq is too slight to slow plans for withdrawing U.S. troops.

In the run-up to June 30, the deadline for U.S. combat troops to leave Iraqi cities, the nation has been rocked by big attacks, including a bombing Wednesday evening in the Sadr City district of Baghdad that killed more than 50.

Still, intelligence analysts, policy advisers and military officers in Washington and Iraq said in a series of interviews that they believe the threat of renewed sectarian warfare is receding — even with the transfer of security control from U.S. to Iraqi hands.