with all due respect
US /wɪθ ɔl du rɪˈspekt/
UK /wɪθ ɔl du rɪˈspekt/

1.
失礼ながら, 恐縮ですが
used as a polite formula preceding a statement of disagreement or criticism
:
•
With all due respect, I think your plan has some flaws.
失礼ながら、あなたの計画にはいくつか欠点があると思います。
•
With all due respect, that's not entirely accurate.
失礼ながら、それは完全に正確ではありません。