The leaders of the Group of 7 countries will share the stage on Friday with leaders from India, Brazil, Turkey and other non-Western countries, showcasing a shifting global landscape on the second day of their summit meeting.

Among the thorny questions on the agenda: migration, which has helped fuel a recent resurgence of populism and far-right parties in Europe and the United States. The leaders will also discuss economic competition with China, security in the Indo-Pacific and relations between the West and the countries known collectively as the Global South, which broadly includes Latin America, Africa and much of the Middle East and Asia.

Prime Minister Giorgia Meloni of Italy, who is hosting the meeting, said the goal of her expanded guest list was to “strengthen dialogue with the nations of the Global South.” She insisted that the Group of 7 was “not a fortress closed in itself,” but “an offer of values that we open to the world.”

Prime Minister Fumio Kishida of Japan also emphasized the importance of strengthening relations with partners beyond the group, in particular the Global South, as the world faces challenges like Russia’s invasion of Ukraine and the war between Israel and Hamas, which threatens to spread to Lebanon.

Much of the focus will be on leaders like Prime Minister Narendra Modi of India and President Luiz Inácio Lula da Silva of Brazil, an acknowledgment that the West is less dominant demographically and economically in the world than in the past, and that it is listening to calls for more equity and balance in major decisions.

Topics will include economic security, Africa, the southern Mediterranean and the challenges posed by artificial intelligence.

How to control migration has vexed the United States and Europe for years, compounded by the effects of climate change and warfare in Afghanistan, the Middle East and Ukraine. It is a particularly sensitive issue for Ms. Meloni, who has campaigned hard to fight what she has called “uncontrolled immigration” to Italy and other parts of Europe from Africa and the Middle East.

While Europe has welcomed thousands of Ukrainians, especially women and children, fleeing the Russian invasion, Ukrainian officials have urged European counterparts to help them repatriate men of fighting age.

But much of the day will be taken up with one-on-one meetings between the leaders, including with Pope Francis, who was invited to attend by Ms. Meloni. After he delivers a speech, Francis will meet with President Biden, Mr. Modi, Mr. Lula, President William Ruto of Kenya, President Recep Tayyip Erdogan of Turkey and President Abdelmadjid Tebboune of Algeria.

Mr. Biden is expected to leave Italy on Friday evening, after a one-on-one meeting with the pope. The leaders will conclude the day with a concert and an informal dinner. On Saturday, there will more bilateral meetings and closing news conferences by the leaders.