| Clue | Source | Date |
|---|---|---|
| Once ref roughed up by Royal Engineers, impose rule again | The Guardian Cryptic | 07 Nov 2023 |
| Again impose eco-squad, say, with gallons going to waste | The Telegraph Toughie | 15 Aug 2019 |
| Implement it again to repel blunder by head of Norwegian police | Irish Times Crosaire | 23 Mar 2016 |
| Strengthen |