Stormzy, Post Malone and Liam Gallagher are confirmed acts to headline the twin events, which will run on the August Bank Holiday weekend from 27-29 August.
It follows the publication of England’s roadmap out of lockdown, which says the government plans to remove all legal limits on social contact by 21 June.
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In a post on Reading and Leeds festivals’ official Twitter page, organisers said: “Following the government’s recent announcement, we can’t wait to get back to the fields this summer. LET’S GO.”
They also shared a short video showing festival-goers in previous years, enjoying fairground rides and gathered in large crowds dancing to music.
Bosses have yet to confirm detailed plans for the events, or whether contingency plans incorporating social distancing measures will figure in the festivals’ organisation.
The last time the festivals took place was in 2019 – with a capacity of over 100,000 people per day at the Reading site and tickets selling out a month before the event.
The festivals had an enforced fallow year in 2020, due to COVID-19 restrictions.
Although confirmation of the 2021 event has only just come, tickets have been on sale since last summer.
Other big acts at the three-day event include Catfish and the Bottlemen, Disclosure and Queens of the Stone Age.
In January, Europe’s largest live music event – Glastonbury – was cancelled for the second year running.
Organisers Michael and Emily Eavis said despite “efforts to move heaven and earth”, the 2021 festival at Worthy Farm would not go ahead, and tickets would again roll over to the following year.
While the recent reveal of the government’s roadmap out of lockdown has provided a framework for potential events over the coming months, many festivals have said they need assurance to allow them to go ahead with plans.
Outdoor performances with a maximum of 4,000 people will be allowed from 17 May as part of the roadmap.
However, the route out of lockdown will depend on coronavirus cases, deaths and hospital admissions continuing to fall, and just a week’s notice will be given before full confirmation of each step.
Festivals which would take place ahead of 21 June – including Isle of Wight and Download – are yet to confirm whether they go ahead.
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Speaking ahead of the Reading and Leeds announcement, chief executive of the Association of Independent Festivals, Paul Reed, told Sky News: “We need urgent intervention on insurance. We’re very appreciative to have a ‘no earlier than date’. But if festivals are to go ahead, we need that intervention before the end of March.
“If that doesn’t happen, unfortunately, you’re not going to see much of the festival sector this year and [it] will therefore need support until when we’re able to return beyond this.”