Foreign Office minister Baroness Warsi has resigned from the government, saying she can "no longer support" its policy on Gaza.
She wrote on her Twitter feed that she was leaving with "deep regret".
Lady Warsi, who was previously chairman of the Conservative Party, became the first female Muslim cabinet minister when David Cameron took office in 2010.
She grew up in Dewsbury, West Yorkshire, and worked as a solicitor before entering politics.
Lady Warsi was demoted from the cabinet to a middle-ranking Foreign Office post in 2012. She was made minister for faith and communities at the same time.
She wrote on Twitter on Tuesday: "With deep regret I have this morning written to the Prime Minister & tendered my resignation. I can no longer support Govt policy on #Gaza."
One of five daughters of Pakistani immigrants, Lady Warsi studied at Leeds University, later working for the Crown Prosecution Service before setting up her own legal practice.