US President Donald Trump blasted Democrats as "anti-Israel" and "anti-Jewish" Friday after they passed a congressional measure opposing hate speech in general instead of specifically condemning alleged anti-Semitic comments by a Muslim congresswoman.

His remarks follow days of tense debates in Congress addressing sensitive questions about national allegiance, discriminatory tropes aimed at Jews, and accusations of show votes that failed to call out a member for controversial comments.

The resolution was originally intended to deliver a direct rebuke of anti-Semitism following comments by a Muslim Democratic congresswoman, Ilhan Omar, that were deemed anti-Semitic and offensive by many colleagues

But after blowback from progressives, it was revised to broadly condemn discrimination against Muslims and other minorities as well.

Trump seized on the shift. "The Democrats have become an anti-Israel party, they've become an anti-Jewish party," he said.

Omar, a Somali refugee who resettled in Minnesota, had sparked fiery debate with her repeated criticisms of Israel and how a powerful pro-Israel lobby in Washington exerts influence on US politicians.

"I am told everyday that I am anti-American if I am not pro-Israel. I find that to be problematic and I am not alone," Omar tweeted.