BAGHDAD — The U.S. has agreed to deploy more than 200 additional troops to Iraq and to send Apache helicopters for the first time into the fight against the Islamic State group in Iraq, U.S. defense officials said Monday.

The decisions reflect weeks of discussions with commanders and Iraqi leaders, and a decision by President Barack Obama to increase the authorized troop level in Iraq by 217 forces — or from 3,870 to 4,087.