MUMBAI, India — As Prime Minister Narendra Modi of India prepares for a big trip to the United States, human rights groups and three Nobel Peace Prize winners have criticized the Bill & Melinda Gates Foundation for its plan to bestow a prestigious award upon Mr. Modi next week during his visit.

The Nobel laureates sent a letter to the Gates Foundation stating that under Mr. Modi’s leadership, “India has descended into dangerous and deadly chaos that has consistently undermined human rights, democracy.’’

“This is particularly troubling to us as the stated mission of your foundation is to preserve life and fight inequity,” said the letter signed by Mairead Maguire, a peace activist from Northern Ireland; Tawakkol Abdel-Salam Karman, a Yemeni journalist and politician; and Shirin Ebadi, an Iranian lawyer and political activist.

The controversy threatens to cast a shadow over Mr. Modi’s much anticipated visit to the United States, which begins this weekend and includes meetings with oil executives, a speech at the United Nations and a planned appearance with President Trump at an Indian diaspora event in Houston called Howdy, Modi!