(Reuters) – Water from the reservoir of a breached Ukrainian dam is still being pumped to the Zaporizhzhia nuclear power plant to cool reactors and other areas, though levels are at values earlier thought to make it impossible, the U.N. atomic watchdog said on Thursday.

The plant, occupied by Russia since the early days of its invasion last year, can fall back on other water sources when the reservoir’s water is no longer available.

These include a large cooling pond above the reservoir with several months’ worth of water, the International Atomic Energy Agency said.

“In these difficult and challenging circumstances, this is providing some more time before possibly switching to alternative water supplies including the large cooling pond next to the plant,” IAEA chief Rafael Grossi said in a statement.

He repeated earlier warnings that the security situation surrounding the Zaporizhzhia facility “remains very precarious and potentially dangerous”.

The destruction of the Kakhovka hydropower dam, also under Russian control since the early days of the invasion, has flooded towns downstream, forced thousands of people from their homes and triggered substantial environmental difficulties.

Russia and Ukraine have traded accusations for more than a year of shelling and endangering safety at the Zaporizhzhia plant. Each side has also blamed the other for the breaching of the Kakhovka dam.

The IAEA said on Tuesday there was sufficient water available to cool the nuclear plant for months.

Grossi is due to visit the Zaporizhzhia plant next week — his third visit to the facility since the Russian invasion in February 2022.