Domestic pressures in U.S., Iran threaten slow-moving nuclear talks

U.S. Secretary of State John Kerry (L), Iranian Foreign Minister Javad Zarif (R) and EU envoy Catherine Ashton pose for photographers before a meeting in Vienna November 22, 2014. REUTERS/Leonhard Foeger

VIENNA/WASHINGTON (Reuters) - A seven-month extension in talks between world powers and Iran on a deal to curb its nuclear programe emboldened critics in Washington and Tehran, threatening to undermine further talks.

After failing to clinch an agreement that would limit Iran's nuclear programme in return for lifting stifling U.S.-led economic sanctions, the sides agreed on Monday to push back, yet again, a deadline for reaching a deal, until next July.