Obama is not attending the gathering of delegations from 20 nations and won't meet with foreign dignitaries who do. He is deferring to President George W. Bush and avoiding putting himself in a situation where he might be seen as trying to represent the United States before his Jan. 20 inauguration.
Obama's transition team on Wednesday said Leach, who endorsed Obama during the campaign, and Albright will mainly be listeners on the periphery of the meetings.
Albright was secretary of state during the administration of former President Bill Clinton. Leach spent 30 years in Congress before being defeated by a Democrat in 2006.
Bush called the summit before the election, and it is expected to draw representatives from the world's 20 largest industrialized nations and emerging economies.
The aim of the Saturday summit is for world powers to craft remedies to the global financial crisis.
"We have one president at a time, and it's important that the president can speak for the United States at the summit," John Podesta, Obama's transition chief, told reporters Tuesday. Podesta noted that Obama had urged such a summit during the presidential campaign.
Obama has been in touch with many foreign leaders.
In phone calls last week, Obama accepted congratulations from leaders of countries including Canada, France, Italy, Pakistan, Saudi Arabia, and Spain. The global financial crisis was among the topics he discussed with key U.S. allies, aides said.
On Tuesday, he spoke with President Luiz Inacio Lula da Silva of Brazil, Pope Benedict XVI, Prime Minister Manmohan Singh of India, King Abdullah II of Jordan and President Mwai Kibaki of Kenya, the homeland of Obama's father.
The president-elect held his first news conference last Friday after he and Vice President-elect Joe Biden met privately with economic advisers. Obama's message: "We are facing the greatest economic challenge of our lifetime, and we're going to have to act swiftly to resolve it."
A new Associated Press-GfK poll found nearly three quarters of Americans now saying they think Obama will make the changes needed to revive the struggling U.S. economy after his inauguration on Jan. 20.
That's a greater percentage of people expressing confidence in the Obama's campaign message of hope and change than the 52 percent who actually voted for him a week ago.
It includes 44 percent of Republicans - an indication that many people who did not pick him are caught up in the wave of optimism that has swept the country since the 47-year-old Illinois senator's groundbreaking election to the highest office in the country.