LONDON/JOHANNESBURG - Gabon's dollar-denominated bonds fell as much as 14 cents on Wednesday after the military said it had seized power in the west African nation, Tradeweb data showed.

The 2025 maturity fell the most, before recovering about 2 cents to trade down 12.488 cents on the dollar at 80.423 cents at 0815 GMT. Its two 2031 maturities were both down around 9 cents.

A group of senior military officers in Gabon claimed to have seized power in the early hours of Wednesday, minutes after the Central African state's election body announced that President Ali Bongo had won a third term.

Gabon completed a $436 million "debt for nature" swap earlier this month, where it exchanged parts of the 2025 and 2031 Eurobonds for a "blue bond" maturing in 2038. That fell 2.25 cents on the dollar to 98 cents.

"The immediate risk to bondholders is that sanctions are imposed that complicate things," said Charlie Robertson, Head of macro strategy at FIM Partners.

"Sanctions on Mali didn't have much effect because Mali wasn't that interconnected with the global economy. But if you sanction Gabon, does that complicate payments? I imagine it will."

The events will hurt all bond issuance in Sub-Saharan Africa, including green and blue bonds, Robertson said.

The blue bond, which was meant to generate savings for marine conservation, has political risk insurance from the U.S. Development Finance Corporation (DFC).

The DFC and The Nature Conservancy, a U.S. environmental organisation that advised on the deal, did not immediately respond to a request for comment. Bank of America, which arranged the deal, declined to comment.

(Reporting By Libby George and Rachel Savage; Editing by Amanda Cooper and Conor Humphries)