Saleem al-Jubouri, spokesman for the largest Sunni political bloc in parliament, told Reuters his brothers, Fuad and Ahmed, were killed instantly when armed men opened fire on them in his home province of Diyala.
Elsewhere, inn Basra, in southern Iraq, a British soldier has died while on patrol, the UK ministry of defence in London said on Wednesday.
The soldier, from the 2nd battalion The Rifles regiment, died after a "small-arms-fire attack", bringing too 133 the number of British soldiers killed in Iraq since 2003.
Iraqi officials meanwhile said a report of a bomb killing 18 people, mostly children, on Tuesday in Ramadi was wrong and stemmed from confusion over a similar attack the day before.
"Peace in Iraq will happen when citizens realise that they can express their ideas and views more effectively... than with violence"
JBernar5, Toledo, USA
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The reported killing of so many children had drawn swift condemnation from the president and the prime minister, but Colonel Tariq al-Theibani, security adviser for Anbar province, said the report of the bombing on Tuesday was wrong.
He said 18 people, many of them children, were killed on Monday by a suicide car bomb, as previously reported. The US military had put the death toll from that attack at 15.
Iraq's government and police had reported on Tuesday another bomb near a football field killing 18 people, mostly children.
The US military, which has a heavy presence in Anbar, said it was unaware of such an attack, adding that it had carried out a "controlled explosion" in the western city, also near a football field, that wounded 30 people, including nine children, on Tuesday afternoon.
In other news, the US said on Tuesday it would attend regional conferences on stabilising Iraq to which Iran and Syria have also been invited, opening the way to a dialogue that critics have long demanded.
Washington accuses Iran and Syria of fuelling the violence in Iraq and has spurned suggestions - including in the December report of a high-level Iraq Study Group - that recommended reach out to both to try to stabilise Iraq.
Hoshiyar Zebari, Iraq's foreign minister, said the mid-March meeting would be a chance for Western and regional powers to try to bridge some of their differences.
While visiting Denmark, he said: "Our hope is that this will be an ice-breaking attempt for maybe holding other meetings in the future. We want Iraq, instead of being a divisive issue, to be a unifying issue."
The US state department would not rule out the possibility of US officials holding bilateral talks with Iranians on the sidelines of the planned conferences - a mid-level meeting in March and a ministerial meeting that may be held in April.
But the White House played down the chances of such talks, stressing its position that Iran first suspend uranium enrichment that the US believes is aimed at developing a nuclear weapon, a charge Tehran denies.