The Latvian government has already repeatedly declared that it will not let the Swedish group own both companies, citing competition worries.
If Melngailis proposal is accepted, it would leave TeliaSonera free to execute its "Plan B", to acquire 100% of LMT and develop it as a full-spectrum operator (wireless & fixed wireless voice, wireless broadband, maybe even TV). Against this, Lattelecom will have to compete (despite any formal agreements on management and strategic decision making) with one arm tied behind its back.
Over the next three years, Latvia faces both municipal and national parliamentary elections in a time of political turbulence and the possible rise of new populist political movements. One can hardly expect to have the government as a rational partner. Already, the government has changed its mind several times in the last couple of months about what to do with Lattelecom -- sell, keep, sell again, auction, etc...
All I can say is -- good luck!