Indonesian President Joko Widodo has agreed with Chinese President Xi Jinping that they will advance cooperation on a project to build Indonesia's new capital.

Joko met Xi in the southwestern Chinese city of Chengdu in Sichuan Province for talks on Thursday.

Indonesia's presidential office said the two leaders discussed the construction of a site on East Kalimantan, where the Indonesian capital is to be relocated from Jakarta.

The new capital will be called Nusantara.

China's foreign ministry said Xi told Joko that Beijing will offer cooperation in such areas as so-called new energy vehicles, including electric cars, and smart city technologies.

China has been strengthening economic cooperation with Indonesia through its Belt and Road Initiative, which includes a marquee project of the construction of an Indonesian high-speed railway.

Japan has also begun providing support for Indonesia aimed at improving the quality of its infrastructure.

But competition over infrastructure projects in Indonesia is expected to become fierce. South Korea has stated that it intends to provide assistance for the construction of water purification facilities and roads.