The tech giant's second-generation smartwatch could ship by April, almost a year after its first model went on sale, the report said. The outlet added that Apple has worked to develop an iPhone 6C model with a 4-inch display, and could show it at the event.
Apple declined to comment to CNBC.
The company is developing a new camera and health capabilities for its smartwatch, according to the report. However, it is unclear if those features would be included in the model potentially unveiled in March.
The 4-inch screen on a new iPhone 6C would also appeal to users who prefer a smaller display than the 4.7-inch iPhone 6S and 6S Plus, the report said.
The new Apple Watch or iPhone models would come after the recent launch of the iPad Pro. Some analysts have said that Apple has not inspired enough enthusiasm for products outside of the iPhone.
Apple shares were down modestly Tuesday afternoon.