Visiting Mongolian President Nambaryn Enkhbayar and Prime Minister Shinzo Abe signed a joint action plan Monday pledging expanded bilateral cooperation, including government talks on ways to utilize rich mineral resources in Mongolia.

The two countries will expand a working group under their trade ministries to include the private sector and discuss development of Mongolia's mineral wealth, the action plan says.

"I'd like to welcome (the fact that) Japanese companies, particularly large firms, have shown interest and eagerness in developing the underground resources," Enkhbayar was quoted by a Japanese official as saying during his meeting with Abe.