But with Turkey launching a military operation to implement a so-called de-escalation zone in the province, the head of the Turkish Red Crescent Kerem Kinik expressed hope aid operations could be expanded across the province.
"In Idlib, the humanitarian situation is, unfortunately, one of a large-scale drama," Kinik told reporters in Istanbul.
He emphasised that people displaced by Syria's over six-year civil war had come to Idlib from other cities including Aleppo, Homs, Hama and Damascus.
"In Idlib there are 400 camps and 800,000 people are living in these camps most of which are unfortunately makeshift in nature," he said.
"They cannot produce anything and are dependent on outside help."
He said the population of Idlib -- which has now ballooned to three million with the refugees -- was hit by air raids and fighting between extremist groups.
But the Turkish army last week began an operation aimed at imposing security in Idlib which for the last months has been controlled by Hayat Tahrir al-Sham (HTS), a group led by Al-Qaeda's former Syria affiliate.
The army is setting up observation posts with the aim of implementing a de-escalation zone co-backed by Russia and agreed at peace talks in the Kazakh capital Astana.
- Humanitarian access -
Kinik said that once the "terror groups" are pushed out of Idlib "we will reach all areas inside" the province.
"We will deliver not just aid but God willing build infrastructure, schools hospitals, new housing," he said.
The Turkish Red Crescent is already carrying out cross-border operations to deliver aid into Idlib in coordination with the United Nations.
It has stocked up seven depots inside Idlib province with tents, food and other supplies to help the refugees and prepare for any new arrivals.
Turkey has throughout the Syrian civil war backed rebels seeking to oust President Bashar al-Assad, but is now working increasingly closely with his main ally Russia.
Kinik said that he would at the weekend be meeting with the head of the Syrian Arab Red Crescent in Beirut. "We have just one aim, to make sure there is not one place inside Syria that humanitarian aid cannot reach."