OREANDA-NEWS.  Escalating violence along Iraq's northern crude oil pipeline to Turkey has prevented technicians from fixing damage due to sabotage that has suspended flows since the start of the month, sources from Iraq's North Oil Company (NOC) said.

Baghdad's vital pipeline to Turkey running through al Qaeda heartland Nineveh was attacked 54 times by insurgents last year, sharply restricting exports to world markets from the Mediterranean port of Ceyhan.

Militants attacked maintenance teams, killing two members, and Iraqi security forces - who deem the area unsafe - are preventing other teams from assessing the damage, NOC sources said.

The Iraqi army sent soldiers to defend the area with little success and a high-ranking officer told Reuters there are attempts to repair the pipeline but security cover is needed.

Turkish energy officials told Reuters it was not immediately clear when the oil flow would resume.

Although the pipeline is often bombed, flows were last halted for such a long period in summer, when it shut for most of July and part of June.

The last tanker that loaded Kirkuk crude sailed on March 12 and a subsequent shipment was cancelled as no more oil remained in storage, a regional shipping source said.

Exports of the grade are normally some 300,000 barrels per day (bpd) when the pipeline is operating. Iraq's main crude oil export stream is Basra Light loaded from southern terminals.

The pipeline has a capacity of around 1.6 million bpd but only one of its two conduits has been in operation, with capacity of about 600,000 bpd.