Sen. John McCain says the billions of U.S. aid to Pakistan must come with strings attached.
The top Republican on the Senate Armed Services Committee, which helps to oversee that money, says Pakistan should show it's helping to "prevent the needless deaths of young Americans."
McCain's comment on CNN's "State of the Union" shows the acute frustration in Congress because of alleged ties between Pakistan's intelligence outfit and anti-U.S. insurgents.
U.S.-Pakistan relations have become even more strained after NATO airstrikes killed 24 Pakistani troops along the Afghanistan border. Pakistan retaliated by shutting down U.S. supply lines.
The Arizona lawmaker says the U.S. should "explore all alternatives," although he did not provide specifics.