The presenter avoids using the F-word by saying 'a big blanking deal' (a blank is a space left in a piece of writing). What Biden actually said was 'This is a big fucking deal'. See here and here for more examples of how the American media avoided printing the offending word in full.
1. If someone drops the F-bomb, they use the word 'fuck' (probably by analogy with with dropping the A-bomb).
2. If you tell someone to put a sock in it, you want them to shut (the blank) up.
• Barack Obama's landmark health reforms marred by Biden gaffe (Guardian)