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LONDON, Dec 14 (Reuters) - Abu Dhabi National Oil Co (ADNOC) is closing in on a deal with Austria's OMV to combine two entities in which the companies own stakes to create a chemicals giant, two people with knowledge of the talks said.

In July OMV said it had entered into talks to merge petrochemicals group Borealis - which is owned by OMV and ADNOC in a 75:25 split - and Borouge, which is 54:36 owned by ADNOC and Borealis.

An agreement is imminent between the two sides and could be announced as soon as today, the people said, speaking on condition of anonymity. The emerging entity will be valued around $30 billion, one of the people said.

The framework agreement to be unveiled will include a capital infusion to ensure both parties have the same equity share in the new company, the person said.

ADNOC and OMV declined to comment.

OMV shares spiked higher, last up 3.6%, after Reuters reported that the two sides were close to agreement.

Previously OMV said both Borealis and Borouge would become "equal partners under a jointly controlled, listed platform for potential growth acquisitions to create a global polyolefin company".

The new company would emerge as a global heavyweight with combined annual sales of more than $20 billion. OMV Chief Executive Alfred Stern has described the transaction as having "strong and compelling industrial logic". (Reporting by Alexandra Schwarz-Goerlich, Emma-Victoria Farr and Anousha Sakoui Additional reporting by Ron Bousso and Yousef Saba Editing by Elisa Martinuzzi and Mark Potter)