What a tough situation to be in – my heart goes out to you. Step 1 is to review your rental agreement. Does it make provision for being unable to access the premises? Worth getting clear on the legal position in terms of your rights. Step 2 is the commercial discussion. If paying rent while unable to trade may penalise your business to the point of closing then the landlord is chasing a short term gain for a long term loss. You pay rent now, and then they have an empty space in the future when you are unable to re-open. And there is unlikely to be a rush of new tenants for them to call on. I suggest you develop a negotiating strategy with the landlord that talks them through this situation for you, and has an alternative proposal for them that shows the long term benefits of giving you rent relief now. If you have an adviser such as a lawyer or accountant it might be worth including them in that discussion to support you.
It’s a tough situation but the sooner you can tackle it the better. Kia Kaha.