TUKKA — Officials in Indonesia and Sri Lanka battled today to reach survivors of deadly flooding in remote, cut-off regions as the toll in the disaster that hit four countries topped 1,300.

In Indonesia, there is growing frustration among survivors of catastrophic flooding and landslides over the pace of the rescue effort and aid delivery.

Humanitarian groups said the scale of the challenge was almost unprecedented even for a country that has faced no shortage of natural disasters.

Monsoon rains paired with two rare tropical storm systems, sometimes known in the region as cyclones, dumped record deluges across Sri Lanka, and parts of Indonesia’s Sumatra, southern Thailand and northern Malaysia last week.

The rising figures reflect information that is only trickling in as many regions remain either physically cut off by flood damage or isolated by electricity and communications failures, or both.

“It’s very challenging logistically to respond,” said Ade Soekadis, executive director of Mercy Corps Indonesia, an aid group.

“The extent of the damage and the size of the affected area is really huge.”

The group is hoping to send hygiene equipment and water both from Jakarta and locally.

He said reports of food and water shortages were already “very concerning” and the situation will be “more problematic as time goes by”.