FRANKFURT, June 29 (Reuters) - German carmaker Daimler topped up its underfunded pension assets by transferring a 3.1 percent stake in Renault SA and Nissan Motor Co worth 1.8 billion euros ($2 billion), to its pension fund, the company said on Wednesday.

Daimler said the transfer will result in a onetime positive impact to its 2016 earnings before interest and taxes (EBIT) of about 0.5 billon euros.

Daimler Chief Executive Dieter Zetsche said, "With this contribution we are again reinforcing our pension assets. Our aim in this is to safeguard our employees' pension benefits for the long term. Regardless of the share transfer we will continue the successful strategic alliance with the Renault/Nissan Alliance." ($1 = 0.9016 euros)

(Reporting by Edward Taylor; Editing by Harro ten Wolde) ((Edward.Taylor@thomsonreuters.com; +49 69 7565 1187;))