A prominent Polish-American academic whose scholarship has explored Polish violence against Jews during World War II says Poland's new right-wing leadership is taking "a step back to the dark ages of anti-Semitism" with a threat to strip him of a state honor and other measures.

Poland's president is considering stripping Princeton professor Jan Tomasz Gross of an Order of Merit he received in 1996. The president's office said it received 2,000 letters from citizens asking it to take that step.

Gross has stoked controversy by exposing dark chapters of Polish wartime history.

Gross told The Associated Press on Friday that: "They want to take it away from me for saying what a right-wing, nationalist, xenophobic segment of the population refuses to recognize as facts of history."