Human rights groups are criticizing the United Arab Emirates for its monthslong detention and prosecution of a local human rights activist.

A coalition of nine groups, including Human Rights Watch, issued a statement Thursday regarding the case against academic Nasser bin Ghaith.

Ghaith has been held since August 2015 after tweeting criticism of Egypt, an ally of the UAE, a federation of seven sheikhdoms on the Arabian Peninsula.

The rights groups say Ghaith's detention and prosecution "violate international standards of free speech and freedom of association." The U.S. also has asked Emirati officials to ensure Ghaith faces fair and transparent judicial proceedings.

Emirati officials did not respond to a request for comment.

The UAE, while liberal in many regards compared to its Middle Eastern neighbors, has strict laws governing expression.