DES MOINES, Iowa (AP) — Republican presidential hopeful Newt Gingrich says he is being factually accurate when he calls the Palestinians an "invented" people and says they are the creation of anti-Israel propaganda.

Gingrich's chief rival for the presidential nomination, former Massachusetts Gov. Mitt Romney, says the former House speaker has made a mistake in the description and has made it more difficult for Israelis and Palestinians to negotiate toward peace.

In remarks Saturday night at a candidate debate, Romney said the United States should allow both sides to talk without signaling a preference.

Gingrich responded to the criticism by saying he is speaking as a historian but adds that it's time for a candidate to stand up and call Palestinian leaders "terrorists."

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