WASHINGTON — US President Barack Obama on Friday condemned the use of violence against peaceful protesters in Bahrain, Libya and Yemen and called for universal rights of expression to be respected.

Obama expressed his concern in a statement read to reporters aboard Air Force One by his spokesman Jay Carney, who said the president was getting frequent briefings on Middle East violence from national security aides.

"I am deeply concerned by reports of violence in Bahrain, Libya and Yemen," Obama said in the statement.

"The United States condemns the use of violence by governments against peaceful protesters in those countries and wherever else it may occur."

"We express our condolences to the family and friends of those who have been killed during the demonstrations.

"The United States urges the governments of Bahrain, Libya and Yemen to show restraint in responding to peaceful protests and to respect the rights of their people," Obama said.

Obama's statement came after a fresh upsurge of violence rattled US foes and allies alike in northern Africa and the Gulf.

In Libya, a "day of anger" by opposition groups against Libyan leader Moamer Kadhafi cost at least 28 lives, according to local sources.

In the Western-leaning Gulf kingdom of Bahrain, which hosts the US Fifth Fleet, there was another bloodbath, as security forces opened fire on anti-regime protesters in the capital on Friday, wounding dozens, a day after four people were killed and some 200 wounded.

There was also a new outburst of violence in Yemen, where the government is a vital ally in the US anti-terror campaign.

Anti-regime protesters in the volatile city of Taez were blasted with a hand grenade on Friday, leaving two dead and dozens hurt, as violent clashes also erupted in Sanaa, witnesses said.

Medics in Aden, meanwhile, said three demonstrators were shot dead as police dispersed protests in several areas of the southern port city, which has borne the brunt of the 10 killed in clashes which broke out in Yemen last Sunday.