Billionaire Japanese tycoon and future space tourist Yusaku Maezawa said Monday his tweet promising a cash giveaway of nearly $10,000 was the most retweeted ever. The 43-year-old Maezawa posted a tweet on Saturday promising one million yen ($9,250) in cash each to 100 randomly selected followers who had retweeted it by Monday. The tweet -- now retweeted more than 4.3 million times -- is the most shared in history, according to the entrepreneur. "Hit the new world record. Surpassed Twitter's world record number of retweets (it was 3.55 million RTs before) and more people are still retweeting," wrote the high-profile Maezawa. The previous record-holder was an American teenager in 2017 trying to win a year's supply of chicken nuggets from fast food chain Wendy's, according to media. In October, Maezawa said he paid an undisclosed sum for a ticket on fellow tycoon Elon Musk's SpaceX rocket around the moon as early as 2023. Maezawa will hitch a ride aboard Musk's Big Falcon Rocket, which SpaceX has acknowledged may not be ready for human flight for at least five years. Known as a passionate art collector, he also plans to take around half a dozen artists with him on the trip. Maezawa is chief executive of Japan's largest online fashion store and is the 18th richest person in Japan, with an estimated fortune of $2 billion, according to business magazine Forbes.