I did see some very cheap fares from Tripoli to BKK for £1000 return in First/Business Class. It was on LH/TG. (As you may, Tripoli is home for the famous BA Sydney first class flight for £1500.)

The following fare (I got from www.airfaresbasement.com) was under £1000. Travel is with Qatar airways and Thai:
Airline carrier From To Flight Aircraft Type Class Stops Depart Arrive
Qatar Airways TIP DOH 551 A330 Airbus First 0 13 November, 16:10 21:50
Qatar Airways DOH DXB 108 A320 Airbus First 0 14 November, 07:30 09:30
Thai Airways International Ltd DXB BKK 522 A330-300 Airbus Business 1 17:55 15 November, 05:00
Airline carrier From To Flight Aircraft Type Class Stops Depart Arrive
Thai Airways International Ltd BKK DXB 517 A330-300 Airbus Business 0 26 November, 17:25 21:25
Qatar Airways DXB DOH 115 A320 Airbus First 0 23:45 23:45
Qatar Airways DOH TIP 550 A330 Airbus First 0 27 November, 01:05 27 November, 06:05
Base price per 1 passenger excluding taxes : Adult - 952.69 GBP
Total ticket price for all passengers including taxes is 988.89 GBP.

You will have to fly to Tripoli in the first place. However, the very cheap fare could be worth it.
There is another option but you have to fly on BA to London first and then fly Thai. You may also be able to change the final FRA_TIP flight (on LH) and use it for your next cheap flight from TIP

Airline carrier From To Flight Aircraft Type Class Stops Depart Arrive
British Airways P.L.C. TIP LHR 899 A320 Airbus Business 0 13 November, 16:00 17:55
Thai Airways International Ltd LHR BKK 917 Boeing 747 First 0 21:35 14 November, 15:55
Airline carrier From To Flight Aircraft Type Class Stops Depart Arrive
Thai Airways International Ltd BKK FRA 7818 Boeing 747-400 First 0 26 November, 23:55 27 November, 05:30
Deutsche Lufthansa AG FRA TIP 4120 A320 Airbus Business 0 09:20 27 November, 13:10
Base price per 1 passenger excluding taxes : Adult - 1047.53 GBP
Total ticket price for all passengers including taxes is 1187.73 GBP.