U.S., Iran presidents issue warnings as nuclear talks extended

By Parisa Hafezi and John Irish VIENNA (Reuters) - Iran and world powers gave themselves an extra week to reach a nuclear accord, extending a deadline due to expire on Tuesday, while U.S. President Barack Obama said there would be no deal if all pathways to an Iranian nuclear weapon were not cut off. With talks in the final stretch, Iran's president Hassan Rouhani also spoke out, saying his country would resume suspended atomic work if the West breaks its promises. Iran and six world powers