George Galloway told a former member of Tony Blair and Gordon Brown's cabinets she killed one million people in Iraq.
The former Labour MP, now a Respect MP, turned on Jacqui Smith as they looked ahead to Friday's vote in Parliament on possible UK military action in the Middle East.
Mr Galloway told her that "all the perfumes of Arabia" would not help wash her hands of past UK action's in Iraq.
But Ms Smith told him that if she were still an MP, she would be taking part in Friday's vote and "living up to my responsibility to answer the call of the Iraqi government and people".
And she told her former colleague that "all of your poetry" was not stopping people being killed in Iraq and Syria.
They were talking to Andrew Neil on Thursday's night's This Week, hours ahead of the vote in Parliament.