Syrian dissidents formed on Tuesday a council to coordinate anti-regime protests as the U.N. Human Rights Council decided to probe violations in the government's crackdown on dissent.

The European Union also piled the pressure on President Bashar al-Assad's regime by adopting on Tuesday sanctions against 15 more people and five businesses as diplomats said more measures were in the offing.

Meanwhile U.S. ambassador Robert Ford travelled to the southern province of Daraa, epicentre of the anti-regime protests, six weeks after he undertook a visit to the flashpoint central city of Hama that infuriated authorities.

On the ground, security forces conducted arrests in eastern Syria while tanks were seen heading towards the town of Al-Bukamal near the border with Iraq, activists said.

Dissidents gathered in Istanbul set up a broad-based “national council” to coordinate their campaign to topple Mr. Assad, an activist said in the Turkish city after four days of meetings.

By 33 votes to four, with nine abstentions, the U.N. Human Rights Council passed a resolution in Geneva to “urgently dispatch an independent international commission of inquiry... to investigate alleged violations of international human rights law” in Syria.

Opening the meeting on Monday, U.N. rights chief Navi Pillay told the council that 2,200 people had been killed since protests began in Syria.

Council members China, Russia and Cuba opposed the resolution. — AFP