An estimated 370,000 Rohingya Muslims have fled Myanmar since Aug. 25, a UN spokesman said Tuesday.
International Organization for Migration's chief spokesman Leonard Doyle said the humanitarian effort on the Bangladesh border was "clearly at full stretch".
The latest figure for refugees who have crossed from Myanmar's Rakhine state to Bangladesh is a 57,000 rise on the figure given by the UN's refugee agency on Monday.
The refugees are fleeing a fresh security operation in which they have said security forces and Buddhist mobs have killed men, women and children, looted homes and torched Rohingya villages.
According to Bangladesh, around 3,000 Rohingya have been killed in the crackdown.
Indonesia said on Tuesday it will deliver aid including rice, blankets and clothes to Rohingya refugees in Bangladesh.
Indonesian Foreign Minister Retno Marsudi said assistance will be extended to refugees in Chittagong and Cox's Bazaar, as she spoke to journalists at the State Palace grounds in capital Jakarta.
Turkey has been at the fore in providing aid to Rohingya refugees and President Recep Tayyip Erdogan has said he will raise the issue at the UN.
Rohingya described by the UN as the world's most persecuted people, have faced heightened fears of attack since dozens were killed in communal violence in 2012.
Last October, following attacks on border posts in Rakhine's Maungdaw district, security forces launched a five-month crackdown in which, according to Rohingya groups, around 400 people were killed.
The UN documented mass gang rapes, killings -- including of infants and young children -- brutal beatings and disappearances committed by security personnel. In a report, UN investigators said the human rights violations may have constituted crimes against humanity.
