NAIROBI, Kenya — President Obama will forgo the usual tourist safari during his visit here, but his administration on Saturday announced new legal changes intended to help protect endangered wildlife in African nations.

The changes would restrict the sale of African elephant ivory across state lines in the United States while adding new limits to commercial exports. Adding to existing federal laws, the rule changes would amount to a near total ban on the commercial trade of African elephant ivory in the United States.

The focus on wildlife came as Mr. Obama opened a two-day visit here, his first as president. He met with his Kenyan counterpart, President Uhuru Kenyatta, to discuss a wide array of issues, including security given the threat from the Shabab, a violent affiliate of Al Qaeda based in Somalia. And the two hosted an entrepreneurship meeting to promote economic development in this fast-growing region of the world.

But the administration hoped the new elephant ivory rules would show its commitment in a global fight against poaching that has drained countries like Kenya of some of its most-prized natural resources. Over the years, the United States has grown to be the second-largest consumer for poached ivory, while often serving as a conduit for the products to the world’s largest consumer, China. Known for its safaris, Kenya relies on tourism, which makes up 12 percent of its economy.