Margaret Thatcher signed lithograph of the Houses of ParliamentThe only non portrait artwork Margaret Thatcher ever signed Limited edition colour lithograph of the Houses of Parliament, signed by British prime minister Margaret Thatcher Thatcher personally commissioned renowned watercolourist Sandra Walker to create "Parliament" Published in December 1991, just a year after Thatcher stepped down as Prime Minister A superb limited edition colour lithograph, Parliament by Sandra Walker features a view of Big Ben