Mutharika says he is aware that some groups have emerged in the party who are not willing to work with the United Democratic Front (UDF).
"If you do not want to unite with UDF, please leave DPP," said Mutharika, saying he is a president who believes in unity.
The president was speaking during the launch of the much touted $224 million Shire Valley Transformation Program largely funded by World Bank and African Development Bank.
The program is expected to benefit 62, 000 households.
On his part, DPP Vice President for the South, Kondwani Nakhumwa, said some senior members of the party are funning backbiting and lies.
Mutharika and Nakhumwa's sentiments heighten long standing divisions and power struggle in the governing party that is fight to cling to power after the constitutional court nullified Mutharika's win in the May 2019.
The court found that the election was marred by widespread irregularities.
During the event, President Mutharika also took a swipe at international rights body Amnesty International which came out to condemn the arrest of HRDC leaders.