Poland's Prime Minister Mateusz Morawiecki speaks at the Security Conference in Munich, Germany, Saturday, Feb. 17, 2018. (Andreas Gebert/dpa via AP)

Munich - The row between Israel and Poland over Warsaw's new Holocaust law has blown up again at the Munich Security Conference.

Israeli Prime Minister Benjamin Netanyahu said comments by his Polish counterpart Mateusz Morawiecki that there were also "Jewish perpetrators" during the Holocaust was "outrageous."

"Here we have a problem of the inability to understand history, as well as a lack of feeling for the tragedy of our people," Netanyahu tweeted late Saturday, adding that he would speak urgently to Morawiecki.

Earlier this month Poland passed a law mandating fines or imprisonment for people who attributed responsibility to the Polish people or state for Nazi atrocities committed during World War II.

The law sparked condemnation from Israel and other countries, with critics saying it would stifle free speech and could be used by Polish leaders to cast aside cases that prove Polish complicity in crimes committed against European Jews.

Morawiecki was on Saturday asked by a journalist whether Poland would consider him a criminal after he reported that Polish neighbours betrayed his Jewish family to the Gestapo, Nazi Germany's secret police.

"Of course it would not be punishable or criminal if you say there were Polish perpetrators, just like there were Jewish perpetrators, like there were Russian perpetrators like there were Ukrainians, not just German perpetrators," the Polish leader replied.

The World Jewish Congress also condemned Morawiecki's comments, with the organisation's president Ronald S Lauder calling them "absurd and offensive" and demanding an immediate retraction and apology from Poland.