WASHINGTON — Making good on a campaign promise to hold a yearly summit with American Indians, President Barack Obama told tribal leaders Thursday gathered in Washington that he is determined to reverse the federal government's history of marginalizing Indian nations.

"You will not be forgotten as long as I'm in this White House," Obama said during opening remarks at the all-day conference of tribal leaders and government officials.

Obama said the meeting is the largest and most widely attended gathering of tribal leaders in U.S. history. Officials planned to discuss problems facing American Indians, including economic development, education, health care, public safety and housing.

Given the government's history of reneging on agreements with Native Americans, Obama said it took an "extraordinary leap of faith" for leaders to attend the meeting. Obama said he is determined to be a good partner with tribal nations.

"We're not going to go through the motions and pay tribute to each other, then furl up the flags and go our separate ways," he said.

Obama signed a presidential memorandum calling on every cabinet agency to give him a detailed plan to improve the relationship between the government and tribal communities.

During his Democratic primary last year, Obama traveled to Indian reservations and promised health care improvements.

"I'll appoint an American Indian policy adviser to my senior White House staff to work with tribes and host an annual summit at the White House with tribal leaders to come up with an agenda that works for tribal communities," Obama said in a video address to the National Congress of American Indians' convention in Phoenix during the final days of his campaign. "That's how we'll make sure you have a seat at the table when important decisions are being made about your lives, about your nations and about your people."

He made good on that pledge, appointing Kimberly Teehee to serve as senior policy adviser for Native American affairs within the Domestic Policy Council. Teehee, a member of the Cherokee Nation, previously served as an aide to Rep. Dale Kildee, D-Mich., and worked for the Democratic National Committee.

He also tapped Dr. Yevette Roubideaux to serve as director of the Indian Health Service within the Department of Health and Human Services, making her the first American Indian to head the federal agency since its founding in 1955. Roubideaux, a member of the Rosebud Sioux tribe, worked for IHS on the San Carlos Indian Reservation and in the Gila River Indian community.

Thursday's event is an opportunity for the administration to promote its $787 billion economic stimulus program. About $3 billion of the economic recovery money went to tribal communities. Obama also has sought budget increases for Indian health care and programs run by the Bureau of Indian Affairs, officials said.

The administration also plans to develop steps with tribes to improve the quality of life on reservations.