The government's "lack of support for international justice" in relation to Gaza conflict was one of the reasons that prompted Baroness Warsi to resign, she said.
She told BBC Radio 4's Today programme: "There was no clear commitment that we would lead the international effort on accountability on both asides for what had happened."
She added: "Our language was not there. It was lagging behind. I don't think it was just words that would have stopped me from doing what I did. I think it was a combination of issues.
"It was the language that we were using, I think it was our lack of support for international justice and accountability for the crimes that had been committed."
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