Young’s has reported steep losses and called 2020 “the most horrible year” in the group’s 189-year history.
Dardis urged the Prime Minister to "not go back on his words" on the June 21 plan.
"We want the PM to honour his commitment he made to the Nation. That is, the 21st June is freedom day. The day we get our lives back,” he said.
Paula Lindenberg, UK President of the Budweiser Brewing Group, said that going forward into reopening the company "would like the government to keep an open dialogue with the industry”.
It came as trade body the British Beer & Pub Association (BBPA) revealed that pub operators have invested a total of more than £285 million in supporting leased and tenanted publicans.
The body said it found the investment "came in the form of rent and other costs waived or reduced during the COVID-19 pandemic, and is in on top of significant financial support to help ensure pubs are Covid-secure and can start to re-open outdoors on Monday".
Operators helped pay for al-fresco dining set-ups for pub gardens, such as marquees, tepees, outdoor heaters and outdoor beer pumps and fridges.
BBPA chief executive, Emma McClarkin, said the investment "shows we are ready to get back open for business", and called on the government to give support the body believes will be "crucial" to the sector’s long-term recovery - including "long term cuts to beer duty, VAT and business rates".