US drone delivery start-up Zipline is in early talks to raise about $1 billion (£750m) at a valuation of roughly $20bn, Bloomberg reported, nearly tripling its valuation at the time of a funding round earlier this year.

Venture capital firm Paradigm, a previous investor, is in discussions to lead the round, with previous backer Tiger Global Management also considering participation, the report said, citing unnamed sources.

Zipline, founded in 2014, promises speedy aerial deliveries using a two-part drone that lowers items to the ground in a pod attached by cable to a larger unit hovering up to 300 feet in the air.

Drone deliveries

The company was valued at $7.6bn in an $800m financing round earlier this year that aimed to boost its commercial deployment.

Its customers include Chipotle and Jimmy John’s restaurants and Walmart.

In August, Uber said it would begin food deliveries through Zipline later this year, in a deal that included an undisclosed investment in the San Francisco-based drone firm.

Uber partnership

Uber similarly invested in Israeli drone start-up Flytrex when the companies began working together late last year.

The companies said they’re targeting 1 million drone deliveries per day by the end of 2029. Zipline has so far made a total of nearly 3 million deliveries across all its markets.

The deliveries are to begin in Zipline’s existing US areas of operation before expanding into other cities.