Warren Buffett has overtaken Bill Gates to become the richest American in the Forbes 400 list, Bloomberg said, citing a recalculated list to be published later this month.

The magazine, in its October 27 issue, recalculates the effect of September's financial news on the wealthiest Americans, those who make up its Forbes 400 list, the agency said.

The Berkshire Hathaway Inc chairman added $8 billion to his net worth in a 33-day period, August 29 to October 1, to reach $58 billion, the agency said, citing the magazine.

Buffett overtook the Microsoft Corp co-founder, whose net worth declined $1.5 billion to $55.5 billion during the 33-day period, the agency said.

Bill Gates had been number 1 on the Forbes list for 15 consecutive years, the agency said.

Las Vegas Sands Corp Chief Executive Sheldon Adelson's net worth declined $4 billion during the period, the steepest drop among Americans who lost $1 billion or more during the credit crisis, the agency said.-Reuters