You can gift any amount you like from income as long as you can meet all your regular needs and not have to draw on your capital.
For instance Income after tax from pension, work, interest 45,000
Regular expenditure food, housing ,clothing, whatever £30,000
So you can gift 15,000 over the year without it being considered deprivation of assets.
What you can’t do is gift over £3,000 and then take a saved sum to pay the gas bill.
It would need to be a regular sum which could be clearly seen to be coming out of income ie through bank payments. But I think that is the sort of thing you’re thinking of?