Assuming you don't want to use your bank account to top up your paypal card / account:

Make sure your credit card is confirmed (they debit a few pence from the card and you have to tell them how much). Then remove your bank account details completely and add them again, without confirming it. Your PayPal account will still remain verified with high limits because of the confirmed credit card.

Then the only option available when you come to top up now is your credit card, but you can still withdraw money to your unconfirmed bank account.