Japan has signed a memorandum of understanding to enable the import of rare-earth minerals from India, a move that will help Tokyo to reduce its heavy reliance on China for the key resources used to manufacture high-tech products.

The signing ceremony took place Friday in Tokyo, although Indian Prime Minister Manmohan Singh postponed his planned visit to Japan because of Prime Minister Yoshihiko Noda's decision to call a general election next month.

"Our prime minister had to postpone his visit, but it was very important that we go ahead and sign this important document," Indian Ambassador to Japan Deepa Gopalan Wadhwa told Nobuhiko Sasaki, vice minister for international affairs at the trade ministry, prior to inking the deal.

Shipments of rare earths from India are expected to begin arriving in Japan as early as next spring, officials at the industry ministry said. With rare-earth production at full throttle, India could supply around 4,100 tons a year, equivalent to roughly 10 percent of Japan's peak annual demand.

The production and exports will be conducted by a joint venture between Toyota Tsusho Corp. and state-run Indian Rare Earths Ltd.

Japan imported around 90 percent of its rare-earth supplies from China last year, and is hoping to reduce its dependence because of the risk that Beijing might curb exports amid the Senkaku Islands rift.