Cluster bombs (file photo)

A U.S. Defense Department memo says the United States will begin using cluster bombs that pose less danger to civilians, after international pressure to change its use of the controversial weapon.

A three-page Defense Department memo requires that, effective in 2018, 99 percent all the bomblets dispersed by a cluster bomb would detonate on impact.

Cluster bombs explode in mid-air and scatter hundreds of smaller bombs over a wide area. Currently bomblets that do not explode on impact can remain active for years, often killing or maiming unsuspecting civilians.

The Defense Department memo says the United States will also begin reducing its inventory of cluster bombs that do not meet the new safety requirements.

The change was made after the United States boycotted a May conference in Dublin, during which 111 countries agreed to ban the use of cluster bombs.

The United States opposed the ban saying cluster bombs are an effective weapon that can help save the lives of both soldiers and civilians.

The Dublin Treaty requires countries to destroy their cluster bomb stockpiles within eight years, stop selling cluster bombs and discourage their use.

Some information for this report was provided by AP.