Williamson announced plans to invest 7 million pounds (8 million euros, USD 9 million) in the drones, saying he expected squadrons "capable of confusing and overwhelming enemy air defences" to be ready by the end of 2019.
Williamson also said Britain would spend 65 million pounds in "offensive cyber", and bring two new naval vessels into service for operations from crisis support to conflict.
Opposition parties criticised Williamson's rhetoric.
Britain is weeks away from its scheduled departure from the European Union and still has no firm arrangements in place.
Prime Minister Theresa May's Downing Street office played down another of Williamson's suggestions, to deploy Britain's new aircraft carrier, HMS Queen Elizabeth, in a challenge to China in the Pacific.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)