ExxonMobil (XOM 0.23%) announced in a press release that it has signed an agreement with Russian oil major Rosneft to establish a joint venture to explore the production of tight oil reserves in western Siberia.

The Russian firm will hold 51% of the joint venture and provide much of the manpower and infrastructure for the project. ExxonMobil will have the minority stake, and bring its technology and engineering know-how, plus financing of up to $300 million. The project will take place at Rosneft's 23 license blocks. These cover a total area of more than 10,000 square kilometers (3,861 square miles).

Drilling is to begin in 2013.

In a separate ExxonMobil press release, the company said that it, and Rosneft, had also signed a declaration to protect the environment and biodiversity of the Russian Arctic continental shelf in their endeavors in the region.