Thousands of women will die from unsafe abortions and millions will have unwanted pregnancies following U.S. President Donald Trump's decision to ban U.S.-funded groups from discussing abortion, activists said Tuesday.

Trump reinstated the so-called global gag rule on Monday, affecting American nongovernmental organizations working abroad, to signal his opposition to abortion, which is difficult to access legally in many developing countries due to restrictive laws, stigma and poverty.

"Women will go back to unsafe abortion again," said Kenyan campaigner Rosemary Olale, who teaches teenage girls in Nairobi slums about reproductive health. "You will increase the deaths."