Unnamed sources gave the estimate to Bloomberg, with a UBS spokesman explaining that the figure given to the news provider is only "slightly higher" than the bank's own forecast.
The division, which covers sectors such as foreign exchange and emerging markets, has hired around 350 people in the past year.
Simon Maughan, an analyst at MF Global Securities, said: "The new hires and position-taking in the first quarter delivered fixed-income revenue ahead of targets."
UBS is set to publish its official results for the first three months of the year on May 4th.
Earlier this week, an article in the Financial Times stated that UBS, along with a number of other financial firms, is seeking to expand its operations in Asia through the hiring of new employees in the region.
By Tony Aynsley