US Secretary of State John Kerry has said that Washington continues to be sceptical about Iran's willingness to roll back its nuclear programme.
"We are not blind, and I don't think we're stupid," Mr Kerry told NBC's Meet the Press programme.
His comments come a day after talks between Iran and six world powers on the programme ended without resolution.
The Israeli PM said he was trying to persuade leaders of the powers not to rush into a "bad agreement".
Benjamin Netanyahu said he recognised that there was a "strong desire" for a deal with Iran, but that governments should wait and "seriously consider things".
The West has long suspected Iran of aspiring to have nuclear weapons but Tehran says it is only enriching uranium for civil purposes.
Under the deal floated in Geneva, Iran could freeze expansion of its nuclear activity in return for limited relief from international sanctions which have been in place for years.
'Serious and capable'
Progress was made in the talks between Iran and the US, UK, France, Russia, China and Germany (known as the P5+1) which ended on Saturday, although a hoped-for deal was not reached.
The two sides will meet again on 20 November.
Mr Kerry said the US was "absolutely determined" that the deal would be a good one.
"Some of the most serious and capable, expert people in our government, who have spent a lifetime dealing both with Iran as well as with nuclear weapon and nuclear armament and proliferation, are engaged in our negotiation," he said.
"I think we have a pretty strong sense of how to measure whether or not we are acting in the interests of our country and of the globe, and particularly of our allies like Israel and Gulf states and others in the region."
Earlier UK Foreign Secretary William Hague told the BBC that a deal could be reached.
The outline of an agreement was "on the table" and it was vital to keep up momentum, he said, although he acknowledged current talks were "formidably difficult".
Asked why the negotiations had apparently stalled, Mr Hague said there were "still some gaps" between Iran and other leading members of the international community, including the US, UK and Russia.
Iranian Foreign Minister Mohammad Javad Zarif has said all sides can "build on" the dialogue in Geneva and there was "the impetus to reach an agreement".
President Hassan Rouhani, speaking to parliament, reiterated that Iran's right to use nuclear technology, including uranium enrichment, was a red line that must not be crossed.
Meanwhile, a member of Jordan's ruling family has said there is the potential for a "really serious breakthrough" at the next scheduled talks on 20 November.
Prince Hassan Bin Talal told the Dermot Murnaghan show on Sky News there were "many enemies" who stood in the way of a possible agreement but a resolution would have major implications for the security of the region.
"I think this is the first step towards a regional architecture for a conference on security and co-operation," he said.