CAIRO ? The latest round of talks between three key Nile basin countries have failed to resolve a contentious dispute over construction of a giant $4.6 billion hydroelectric dam in Ethiopia, Sudan's irrigation minister said. The yearslong dispute over the Grand Ethiopian Renaissance Dam on the Blue Nile pits Ethiopia's desire to become a major power exporter and pull millions out of poverty against Egypt's concern that the dam will curtail its critical share of the river if filled too quickly. Sudan has long been caught between the competing interests of Egypt and Ethiopia. It stands to benefit from Ethiopia's dam, including having access to cheap electricity and reduced...