Congressman Carlos Marun of the Brazilian Democratic Movement Party will replace Antonio Imbassahy as the minister in charge of relations with Congress, the sources said.
A government press representative said there was no decision on Imbassahy's potential replacement and that discussion of a possible swap was ongoing.
Imbassahy's Brazilian Social Democracy Party (PSDB), the largest allied party in Temer's coalition, has distanced itself from his administration ahead of next year's elections, when it plans to run its own presidential candidate.
The move would be the latest step in a cabinet reshuffle meant to gather political backing for Temer's plans to streamline the nation's social security system and reduce government spending.