TOKYO (Reuters) - Some six months after his visit to Donald Trump’s Manhattan mansion cheered investors, Masayoshi Son, Japan’s richest man, is set to follow his friend to Saudi Arabia as the new U.S. president makes his first overseas trip since taking office.

FILE PHOTO: SoftBank Group Corp Chairman and CEO Masayoshi Son attends a news conference in Tokyo, Japan, February 8, 2017. REUTERS/Toru Hanai

Son, head of Japan's SoftBank Group Corp 9984.T, travels to Riyadh this weekend where he is expected to announce the close of the first fundraising round for what will be the world's biggest private equity fund, backed by Saudi Arabia's sovereign wealth fund and Apple Inc AAPL.O.

His appearance in the Saudi capital and the expected launch of the $100 billion Vision Fund coincide with Trump’s official visit to the kingdom, one leg of a presidential trip that also includes Israel, Belgium and Italy.

Son describes the fund as essential for setting up SoftBank for a data “gold rush” which he expects to happen as the global economy becomes increasingly digitized.

“The Vision Fund has created a framework for SoftBank to grow over the next 100, 200 and 300 years,” Son said in February. “The next 10 years would be the time for me to put the plan into practice while grooming successors.”

Son is scheduled to attend a forum of global chief executives in Riyadh on Saturday to be held on the sidelines of the Trump visit, a list of attendees showed.

A SoftBank spokesman declined to comment on Son’s schedule.

The aggressive dealmaker made headlines in early December when he appeared in the marble lobby of Trump Tower in New York alongside the then president-elect, dressed in a red vest and near-identical red tie to the tycoon-turned-commander-in-chief.

He was among the first in a series of Asian billionaires and leaders to pay tribute to Trump, who won office in November on a platform that focused heavily on national security and protecting American jobs.

Son’s pledge to Trump to invest $50 billion in the United States and create 50,000 new jobs was light on details but spoke to the president’s election promise to boost economic growth by making deals with individual companies, rather than through complicated trade deals.

SoftBank Group shares surged after Son’s December meeting with Trump and his announced investment.

Foreign tycoons who paid homage to Trump after Son include Foxconn founder Terry Gou and Alibaba boss Jack Ma, who are both close business partners of Son. In November, Japanese Prime Minister Shinzo Abe visited Trump in New York, less than two weeks after the U.S. election.