US Army Secretary Dan Driscoll has submitted his resignation after about 18 months in the role.

Dan Driscoll, the United States army secretary, has resigned from his role and will leave the Pentagon in the coming days.

The number of people missing in Nepal has risen to more than 4,200, the national disaster agency said on Monday.

The death toll from last week's devastating floods in Nepal has risen to 903, while the number of people reported missing has nearly doubled to 4,247, according to authorities

At least 781 people have been killed and more than 2,500 remain missing after a glacier collapse sent mud and debris through mountain valleys.