Nepalese pedestrians walk during the monsoon rains in Boudhanath Stupa on the outskirts of Kathmandu. The monsoon has caused a rise in river levels in Nepal.

Katmandu, Nepal - Officials say heavy monsoon rains have swollen two major rivers in Nepal and increased the threat of widespread floods in the Himalayan nation.

The National Emergency Operation Centre in Katmandu said both the Mahakali river in the west and Kosi river in the east have reached the highest water level for this year.

The Kosi river located 400km south-east of Katmandu is known for flooding large areas in Nepal and across the border in India.

The Centre said on Friday that local authorities have posted red flags in the area to warn villagers the river could breach its banks and inundate the villages. - Sapa-AP