Homebrew fails on MacOS Big Sur

I upgraded from Mohave to Big Sur and found that homebrew is not working any more. I installed the command line tools using the command

xcode-select --install

After I run brew list, I get the following error

~ brew list
Traceback (most recent call last):
    11: from /usr/local/Homebrew/Library/Homebrew/brew.rb:23:in `<main>'
    10: from /usr/local/Homebrew/Library/Homebrew/brew.rb:23:in `require_relative'
     9: from /usr/local/Homebrew/Library/Homebrew/global.rb:37:in `<top (required)>'
     8: from /usr/local/Homebrew/Library/Homebrew/vendor/portable-ruby/2.6.3/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
     7: from /usr/local/Homebrew/Library/Homebrew/vendor/portable-ruby/2.6.3/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
     6: from /usr/local/Homebrew/Library/Homebrew/os.rb:3:in `<top (required)>'
     5: from /usr/local/Homebrew/Library/Homebrew/os.rb:21:in `<module:OS>'
     4: from /usr/local/Homebrew/Library/Homebrew/os/mac.rb:58:in `prerelease?'
     3: from /usr/local/Homebrew/Library/Homebrew/os/mac.rb:24:in `version'
     2: from /usr/local/Homebrew/Library/Homebrew/os/mac.rb:24:in `new'
     1: from /usr/local/Homebrew/Library/Homebrew/os/mac/version.rb:26:in `initialize'
/usr/local/Homebrew/Library/Homebrew/version.rb:368:in `initialize': Version value must be a string; got a NilClass () (TypeError)

I tried by deleting the folder /Library/Developer/CommandLineTools and installing the Command Line Tools for Xcode 12.3 beta but still I am getting the same error. Is there any way to make brew work?