Former US Sec. of State Hillary Clinton
Former US Sec. of State Hillary ClintonReuters

Four weeks from publication of her new memoir, Hillary Clinton on Wednesday robustly defended her record as secretary of state and navigator of hot-button crises like Iran's nuclear drive and elusive Mideast peace.

The book, "Hard Choices," is set for a June 10 release and offers Clinton a framework for criss-crossing the country to boost her public standing as she mulls a possible run for the White House in 2016.  

Clinton told a Washington meeting of the American Jewish Committee that said she spent months holed up in her attic in upstate New York penning her memoir about the pitfalls and progress of conducting diplomacy in more than 110 countries.  

The book - "a light summer read," Clinton quipped - highlights what she described as the "endless set of tough calls" she faced in her four years as President Barack Obama's first secretary of state.

But while hailed as a trailblazer by fellow Democrats, Republicans say Clinton blew many of those calls, arguing that she oversaw a failed "reset" with Russia and ultimately did little to slow Tehran's march toward nuclear capability.

Republican lawmakers also insist Clinton should take the blame for the administration's response to the deadly terrorist attacks on the US mission in Benghazi, Libya, a tragedy she has labelled her darkest time as secretary of state.  

Republican Senator Marco Rubio, himself a prospective 2016 presidential candidate, recently gave Clinton an "F" for her tenure at the State Department.

But she insisted Wednesday her record was a positive one.

"There are always choices that we later regret, consequences that we do not foresee, alternative paths we wish we had taken, but hopefully we get it more right than wrong," she said in her speech.    

Clinton noted how she had worked hand in hand with Obama from 2009 in an effort to resolve the crisis with Iran over its nuclear program, which negotiators from Tehran and six world powers including the United States were discussing Wednesday in crunch talks aimed at hammering out a historic accord.

"We decided to use both engagement and pressure to present Iran's leaders with a hard choice of their own," she said.

She claimed a similar tactic was employed in Israeli-Palestinian peace negotiations, which have since stalled.  

Clinton said that during her tenure she "worked, cajoled and implored" her way to three rounds of face-to-face negotiations between Israeli Prime Minister BInyamin Netanyahu and Palestinian Authority leader Mahmoud Abbas, in a bid to reach a comprehensive two-state solution.