Foreign Secretary William Hague said Iran should "be more realistic about what is necessary" to reach a nuclear deal with major powers.
Hague made the comments shortly after a meeting with US Secretary of State John Kerry in Vienna.
They were joined in the Austrian city by their French and German counterparts for talks about Iran's nuclear programme.
Six months ago, a deadline to reach an agreement was set for July 20.
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Philip Hammond has dismissed concerns that abolishing stamp duty for first-time buyers will push up house prices.
Elsewhere it will be largely sunny, though with gusty winds at times, and a few showers likely in places.
Heavy rain has caused widespread flooding and travel disruption across north west England and North Wales.