Japan's NTT sold a 35.2 percent stake in SLT to Malaysia's UT group this week.
Fitch warned that any action by Sri Lanka's government "which is detrimental to the financial profile of SLT" could trigger a downgrade.
Fitch said the outlook is 'Stable'. SLT's local currency international rating was confirmed at 'BB-' and its domestic rating at 'AAA(lka)'.
The rating on SLT's senior-unsecured notes due in 2009 has been downgraded to 'B+' and a recovery rating 'RR4' has been assigned to the notes.
Fitch said the new shareholder and the Sri Lanka government are expected to decide on the make-up of the board of directors as well as management positions after a mandatory offer to buyout minority shareholders is completed. .