"It's deeply concerning. We were going to watch this closely, and we're going to continue to do everything we can to support the idea of democratic ideals that are expressed by the African people," said White House national security spokesman John Kirby.

Rebel officers in the oil-rich central African state announced earlier Wednesday they had seized power following disputed elections, in which President Ali Bongo Ondimba had been declared victor.

The political demise of Bongo -- who has been placed under house arrest along with other top officials, according to the new military regime -- fits a pattern of coups in French-speaking Africa in recent years.

In Mali, Burkino Faso and latterly Niger in the northwest Sahel region, new military governments have taken openly hostile positions towards France, tapping into resentment felt by many locals about the former colonial power and its ongoing influence.

"Official France -- its army, its diplomatic representatives -- are being literally chased out of countries in the Sahel," Jean-Herve Jezequel, an expert on the region at think tank the International Crisis Group told AFP.

In Gabon, the views and politics of the new military regime remain unknown, with the head of the Republican Guard, General Brice Oligui Nguema, thought to be at its head.

*This story was edited by Ahram Online