The planned city of Nusantara is set to begin operating on August 17, replacing traffic-clogged and sinking Jakarta as Indonesia's new capital.

But contractors, whose work building the city has been hampered by daily rains, asked authorities to carry out a weather-modifying operation, said Tri Handoko Seto, a senior official at Indonesia's Meteorological, Climatological and Geophysical agency (BMKG).

"They submitted a request to carry out a weather modification operation so that the rain that occurred every day can be diverted to another place, eliminated in a certain area, or at least be reduced," Seto told AFP.

Cloud seeding, which introduces tiny particles or chemicals to manipulate existing clouds, has gained popularity worldwide as a way to induce rain to combat drought or boost local water supplies.

But scientists say the technique cannot create weather -- nor can it trigger rainfall at the scale observed in countries such as Germany and the United States.

The cloud seeding operation around Nusantara began last week and is due to end on Sunday, followed by an evaluation to determine whether it needs to be continued, Seto said.

It is the first time authorities have used cloud seeding around the planned city to reduce rainfall, he said.

Flooding and landslides are common during the vast archipelago's six-month rainy season and the BMKG has forecast the downpours around Nusantara will last until August.

The Indonesian government aims to have 1.9 million people living in Nusantara by 2045, importing a wave of human and industrial activity into the heart of Borneo.

Environmentalists have warned that the planned city will speed up deforestation in one of the world's largest stretches of tropical rainforest.

Thousands of civil servants are expected to move to the city in September to begin work but Jakarta's plan has already been delayed by several months due to slow construction.