Manama: Bahrain`s crown prince has vowed to hold a national dialogue, after security forces opened fire on anti-regime protesters in the capital amid reports that up to 55 people had been wounded.
The brutal crackdown, which followed an army pledge to restore order through "strict measures" after a deadly police raid, led the United States and Britain to ask nationals to avoid all but essential travel to the Gulf kingdom.
Crown Prince Salman bin Hamad al-Khalifa promised to open a sweeping national dialogue once calm returns, and soon afterwards King Hamad formally announced that he had assigned his heir to start those discussions.
US President Barack Obama condemned the violence in a phone conversation with the king, a key regional ally of Washington.
Obama said "the stability of Bahrain depends upon respect for the universal rights of the people of Bahrain, and a process of meaningful reform that is responsive to the aspirations of all Bahrainis," according to a White House statement.
Bahrain is of vital strategic importance to Washington because the US Navy`s Fifth Fleet is based there and some 40 percent of the world`s oil passes through the Gulf.
The prospect of a prolonged crisis raises fears of a potential flashpoint between Iran and its Gulf Arab rivals, if the Islamic republic attempts to capitalise on the protest led by the disaffected Shiite majority.
Iran "condemned the violent confrontation" and asked the Bahraini government to show self-restraint.
Hardliners in predominantly Shiite Iran have often expressed kinship and support for Bahrain`s Shiites. The royal family are Sunnis.
Marchers had been trying to reach Pearl Square, the epicentre of pro-democracy protests that have shaken the Gulf island state, when the forces opened fire.
Witnesses said the gunfire was targeting them near Salmaniya hospital, about two kilometres (one mile) to the south.
In response to protests against his government that have drawn thousands of people on to the streets, King Hamad bin Isa al-Khalifa announced late on Friday the crown price had been granted "all the powers to fulfil the hopes and aspirations of all gracious citizens from all sections" in the national dialogue.
US President Barack Obama spoke with the king on Friday evening, condemning the violence and urging the government to show restraint. Obama said the stability of Bahrain, home to the US Middle East fleet, depended upon respect for the rights of its people, according to the White House.
The unrest has presented the United States with a now familiar dilemma in the region. It is torn between its desire for stability in a long-standing Arab ally and a need to uphold its own principles about the right of people to demonstrate for democratic change.
In a television interview, Prince Salman said "our dialogue must take place in a climate of total calm," adding that "no issue can be excluded from that dialogue."
"What is happening today in Bahrain is not acceptable... We have reached a dangerous stage that necessitates that each of us acknowledges the responsibilities... Bahrain today is divided."
In a statement read on state television, King Hamad charged Prince Salman with starting a "dialogue with all sides and groups in the kingdom with no exceptions."
The statement made no mention of the latest violence.
Earlier, angry Shiites in the nearby villages of Sitra and Karzakan buried the four people killed on Thursday.
Thousands of mourners chanted slogans calling for the ouster of the Sunni al-Khalifa dynasty`s regime, and sang songs urging unity between the Shiite majority and Sunni compatriots.
They shouted "people want to overthrow the regime" -- the slogan used by protesters across the Arab world inspired by uprisings in Tunisia and Egypt that brought down the strongmen of those two Western-backed countries.
A large banner carried in front of the funeral procession of victim Ali Mumen condemned concerns by Formula One chief Bernie Ecclestone that next month`s Bahrain Grand Prix would be affected by the political upheavals.
"Mr Ecclestone, are our lives a price for your Formula One?" it asked, in English.
Meanwhile, hundreds of pro-regime demonstrators marched in Manama after Friday prayers, denouncing the opposition and pledging allegiance to the king.
Britain revoked 44 licences for the export of security equipment to Bahrain because of the risk it might be used to suppress anti-regime protests, the foreign office said.
France also suspended exports of security equipment.