DUBAI/NEW DELHI  - Abu Dhabi National Oil Co (ADNOC) is in talks with several partners, including Saudi Aramco, for possible downstream joint ventures abroad, particularly in Asia, industry sources with knowledge of the matter told Reuters.

The Abu Dhabi state energy company wants to increase its crude refining capacity by 60 percent and boost petrochemical production.

It plans to spend more than 400 billion dirhams ($109 billion) in the next five years, which will include boosting gas output and investing in international downstream activities, the company said in November. 

ADNOC wants to expand its downstream portfolio in markets where demand for oil is still growing, such as China and India, securing a new outlet for its crude.

"As part of ADNOC’s further expansion of our downstream business, we are exploring a number of select international downstream opportunities, especially in growth markets. We will update the market in due course," an ADNOC spokesman said on Wednesday, declining to comment on specific projects.

One source said the opportunities ADNOC could be looking at included a refinery and petrochemical project in India, for which Aramco signed an initial agreement on Wednesday with a consortium of Indian state refiners.

The source said talks were at a very early stage and no decision had been taken. It was not clear whether ADNOC would join Aramco on the same project.

In March, an executive of Indian Oil Corp said ADNOC was interested in buying a stake in its planned west coast refinery. 

Top executives from Aramco and India's Ratnagiri Refinery & Petrochemicals - a joint venture of Indian Oil Corp, Hindustan Petroleum Corp and Bharat Petroleum Corp - signed a memorandum of understanding to take equal stakes in the project in Maharashtra state. 

Aramco may introduce at a later stage a strategic partner to share its 50 percent stake, Saudi Energy Minister Khalid al-Falih said on Wednesday in New Delhi. Aramco Chief Executive Amin Nasser declined to comment on whether Aramco had been in talks with ADNOC for a partnership in the project.

The project includes a 1.2-million-barrels-per-day (bpd) refinery integrated with petrochemical facilities with a total capacity of 18 million tonnes per year.

It will be one of the largest refining and petrochemical complexes in the world, built to meet fast-growing fuel and petrochemicals demand in India and elsewhere, and providing a steady outlet for Saudi crude oil.

(Reporting by Rania El Gamal and Nidhi Verma; Editing by Dale Hudson) ((rania.elgamal@thomsonreuters.com; +971 562 160 434; Reuters Messaging: rania.elgamal.reuters.com@reuters.net ; Twitter: https://twitter.com/Rania_ElGamal))