Barack Obama says the next vice president should be independent and willing to say when the president is wrong.
The US presidential candidate is refusing to give hints on whom he might pick for a running mate, but he has described the qualities he is looking for – and shyness and blind loyalty are not among them.
In an interview shown on NBC’s Meet The Press, he said he would like someone “who’s willing to tell me where he thinks or she thinks I’m wrong”.
The remark comes in the twilight of the Bush White House, an administration famous – and much-criticised – for the value it has placed on loyalty within its ranks.
Whomever he or she may turn out to be, Mr Obama’s running mate will be hired for more than a ceremonial role, according to the candidate.
The only person Mr Obama is acknowledging is on his short list of running mates is his former presidential primary rival, Senator Hillary Clinton.
Meanwhile, Mr Obama, back in his home town after his tour of Afghanistan, the Middle East and Europe, is seeing a doctor to deal with a sore hip.
“His hip has been sore from basketball for a few weeks, so he’s going to see an orthopaedic doctor,” Obama spokesman Robert Gibbs said.
Mr Obama is a life-long basketball player and he squeezes in a game every now and then on the campaign trail.
At one stop during his overseas trip, he shot baskets with US troops in Afghanistan.