Vienna, Jul 13, IRNA -- US Secretary of State John Kerry refused to answer a question on prospects for an extension of Iran nuclear talks, tweeted Boston Globe reporter Matt Viser in Vienna on Monday.

According to a pool report, the following question was posed to the American diplomat: �Secretary Kerry, are you going to extend again?�

The question was reportedly met with silence by Kerry.

The reporter posed again the question: �Can you rule out extending?�

Again silence, said Viser who said all E3 plus foreign ministers 'looked grim.'

By IRNA