A Labour MP has resigned as aide to shadow chancellor John McDonnell after it emerged that she once endorsed relocating the state of Israel to the US.
After the post from August 2014 was revealed by the Guido Fawkes website on Tuesday, Shah released a statement apologising "for any offence it has caused".
But later the Bradford West MP went further and resigned as parliamentary private secretary to McDonnell. In this second statement, she said: "I deeply regret the hurt I have caused by comments made on social media before I was elected as an MP.
"I made these posts at the height of the Gaza conflict in 2014, when emotions were running high around the Middle East conflict. But that is no excuse for the offence I have given, for which I unreservedly apologise.
"In recognition of that offence, I have stepped down from my role as PPS to the shadow chancellor John McDonnell. I will be seeking to expand my existing engagement and dialogue with Jewish community organisations and will be stepping up my efforts to combat all forms of racism, including anti-Semitism."
Campaigners have now raised concerns about Shah's involvement in an anti-Semitism inquiry being conducted by the Commons home affairs committee, of which she is a member.
Jonathan Sacerdoti from the Campaign Against Antisemitism, said: "We have offered to assist the select committee in its work investigating anti-Semitism. However, if Naz Shah remains on the committee it will be hard for those of us giving evidence to take the inquiry seriously."
BuzzFeed News has asked the committee whether Shah will remain on the inquiry.
Labour's leadership has faced accusations in recent weeks that it has been slow to take action against anti-Semitism within the party. Leader Jeremy Corbyn has repeatedly condemned prejudice against Jews.
Emily Ashton is a senior political correspondent for BuzzFeed News and is based in London.
Contact Emily Ashton at email@example.com.
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