DoorDash announced two deals worth billions of dollars on Tuesday, saying it has agreed to acquire Deliveroo, the British food delivery company, and SevenRooms, a platform used by hotels and restaurants to manage reservations and marketing.

The acquisitions would enable DoorDash, the dominant food delivery app in the United States, to expand overseas and add reservation management technology to be used by global businesses.

DoorDash said its agreement to buy Deliveroo, a British food delivery service, in a roughly $3.9 billion deal would give it a larger footprint in Europe and a presence in the Middle East, covering millions of users in more than 40 countries.