Across:
   7. Something Dan sketched in 8 down city (6)
   8. Operated on our piles, which is far from safe (8)
   9. Land reform lies! (4)
  10. Coital lip-licking possibly providing concern for member (9)
  11,20dn. Demonstrations perhaps of 8 down 1968 10 17 (5 6)
  12. With values unchanged by direction East going, poor cities rebuilt (9)
  15,16. 1968 thaw sparing purge possibly? (6 6)
  18. They farm vegetables - an effort! (9)
  19. Partied and ruined grade (5)
  22. Imperial arm is Tsars' offering - they are quick to percieve a 17 (9)
  24. Extremes of candour endow workers as a group (4)
  25. Poles following government programs for health's sake (8)
  26. Dissect parts, ignoring a second's orders (6)
Down:
   1. City does as directed (6)
   2. Perhaps 18 European articles initially cheer girl (10)
   3. Leaves out bins (5)
   4. Silly, petty... poor model (9)
   5. Group of dumb locals (4)
   6. Persecution by union's lawful leaders, along with dishonesty (8)
   8. Shine at being removed from awful hospital (6)
  13. Using dubious logic, chair ruled with a small cohort (10)
  14. Rub men and overwhelm (9)
  15. Cultivated in advance of normal education (8)
  17. Panic as councillor meets with terror group (6)
  20. see 11ac
  21. Non-aligned movement's weak (5)
  23. Chopper is for alliance (4)