The Pentagon is dispatching an additional 13,000 US soldiers to Afghanistan beyond the 21,000 announced publicly by President Barack Obama, in March, a US newspaper reported. The additional forces are primarily support forces - such as engineers, medical personnel, intelligence experts and military police - the paper said, bringing the total build-up Obama has approved for Afghanistan to 34,000. "Obama authorised the whole thing. The only thing you saw announced in a press release was the 21,000," a defence official familiar with the troop-approval process said.