Two Sunni factions in Bahrain say they are suspending participation in talks with Shiite opposition groups because of a spike in violence in the Gulf nation's two-year-old uprising.

The moves are unlikely to disrupt the overall negotiations between Bahrain's Sunni rulers and the Shiite opposition bloc, but it reflects the high level of tension confronting attempts at dialogue.

In letters issued Tuesday, the groups Al-Saff Al-Islami and Al-Minbar Al-Islami say they are protesting the widespread clashes last week during the second anniversary of the uprising. A protester and policeman were killed.

Al-Saff is led by a former intelligence officer. The other represents the Muslim Brotherhood.

Bahrain's majority Shiites are seeking a greater political voice in the Sunni-ruled kingdom, which is home to the U.S. Navy's 5th Fleet. Talks resume Wednesday.