(Reuters) - Brent crude rose above $61 a barrel on Friday, supported by geopolitical tensions in Libya and Iraq, while traders eyed the outcome of Iran nuclear talks for further trading cues.

Fighting has escalated in northeast Iraq where the Islamic State militants have lit up oil wells to deter Shi'ite militiamen and Iraqi soldiers from advancing. In Libya, worsening security conditions have led to the closure of 11 oilfields.

Brent LCOc1 rose 53 cents at $61.01 a barrel by 2235 ET, but was on track for a weekly drop after an 18 percent gain last month. U.S. West Texas Intermediate crude CLc1 was up 34 cents at $51.10 a barrel, set for a more than 2 percent weekly rise.

Concerns over Middle East oil supply widened Brent's premium to WTI CL-LCO1=R by nearly a dollar to close to $10.

"Keeping an eye on production in that region, there are escalating tensions there that could push the spread back through that $13-$14," said Jonathan Barratt, chief investment officer at Ayers Alliance Securities in Sydney. The spread was at its widest in more than a year at $13 on Monday.

Investors are also keeping a close watch on Iran nuclear talks and U.S. non-farm payrolls data due later on Friday.

Iran's foreign minister on Thursday suggested that a 10-year moratorium on some aspects of the country's nuclear program might be acceptable to Tehran, though he declined to discuss the issue in detail.

Any sign of a lasting agreement between Tehran and six world powers could result in a flood of Iranian crude returning to the market.

Positive non-farm payrolls data could strengthen the U.S. dollar against major currencies if it supports the case for a rise in U.S. interest rates in coming months.