diff --git a/electrum/wallet.py b/electrum/wallet.py
index cf68667ae6ac..249b5ffead7f 100644
--- a/electrum/wallet.py
+++ b/electrum/wallet.py
@@ -3362,7 +3362,6 @@ def get_tx_fee_warning(
             txid: Optional[str]) -> Optional[Tuple[bool, str, str]]:
 
         assert invoice_amt >= 0, f"{invoice_amt=!r} must be non-negative satoshis"
-        assert fee >= 0, f"{fee=!r} must be non-negative satoshis"
         is_future_tx = txid is not None and txid in self.adb.future_tx
         feerate = Decimal(fee) / tx_size  # sat/byte
         fee_ratio = Decimal(fee) / invoice_amt if invoice_amt else 0