Proverb: You can't give what you don't have — i.e., you can't help or give money if you don't have any; nothing comes from nothing.
「申し訳ないが貸せない」—「無い袖は振れぬ」と諦めるしかない。
"I'm sorry but I can't lend you anything." — "There's nothing you can do; you can't give what you don't have."
政府も予算が足りないから、無い袖は振れぬと説明した。
The government explained that it couldn't provide more because the budget was insufficient — you can't give what you don't have.