Singh called up the state's Health Minister Himanta Biswa Sarma to enquire about the condition in the state, a PMO statement said.
The Prime Minister assured the Assam government of all help to deal with the flood situation there, it said.
He also announced an assistance of Rs one lakh for the next of kin of each of the deceased from the Prime Minister's National Relief Fund.
The statement said Singh also spoke to Defence Minister A K Antony "urging full army assistance for the rescue and relief operations in the affected areas".
The situation deteriorated in the state today as 23 of the 27 districts came in the grip of floods in which 30 people have died and several are missing.
