The letter, a rare voicing of concern, comes nearly two years after the election of Law and Justice, a deeply conservative, nationalistic and anti-migrant party that is backed by some groups with anti-Semitic views. Observers including the country's human rights commissioner have noted a rise in anti-Semitism and other hate speech and as well as attacks on dark-skinned people since the party came to power.
"We are appalled by recent events and fearful for our security as the situation in our country is becoming more dangerous," Leslaw Piszewski, the head of the Jewish community in Poland, and Anna Chipczynska, the head of the Warsaw community, wrote in the letter.
Chipczynska told The Associated Press on Thursday that the community sent the letter last week to Jaroslaw Kaczynski, the ruling party leader, but so far had no reply. The AP made several attempts to reach the party spokeswoman but all calls went unanswered.
The letter says there has been a "rise of anti-Semitic attitudes in recent months, accompanied by aggressive hate speech and violent behavior that are directed towards our community" and asked Kaczynski to decisively condemn the anti-Semitism.
Among examples it mentions the increasingly visible presence, even at state events, of members of an extremist right-wing group, the National Radical Camp, and an attack last week on a visiting Israeli soccer team.
It also cited a recent comment by a lawmaker from Law and Justice, Bogdan Rzonca, who said on Twitter earlier this month that he wondered "why there are so many Jews among abortionists despite the Holocaust."
Another incident that raised the community's concern was when a journalist for state television TVP, Magdalena Ogorek, highlighted the Jewish ancestry of a senator, Marek Borowski, when criticizing his politics. The incident sparked a wave of critical comments, and the head of TVP demanded an explanation from Ogorek.
Some Polish observers have said the climate evokes the mood in the country in 1968, when the communist regime waged an anti-Semitic campaign against Jews that culminated in thousands being expelled from the country.
"We are afraid for our security and our future in Poland," the Jewish leaders wrote to Kaczynski. "We do not want a return to the year 1968." Poland's Jewish community was the largest in Europe before the Holocaust, with some 3.3 million people. Today's community is much smaller but had been growing amid a new tolerance that came with the collapse of communism in 1989.