KABUL: Afghan President Hamid Karzai has declared that Nato aircraft can no longer fire on homes under any circumstances, an indication that the conflict over Nato air strikes that kill civilians—including one that left 18 dead last week—remains unresolved.

Following an outcry over the attack in Logar province, which killed children, teenagers and adults, Nato imposed new limits on air strikes aimed at houses, but still wants to use them to defend troops on the ground. Karzai and the coalition met last weekend to discuss air strikes that have inadvertently killed Afghan civilians, a politically heated issue.

However, the two sides offer different interpretations about what they agreed upon at the meeting.

The dispute highlights the sensitive relationship between the international force and Karzai. The Afghan president has denounced air strikes that have caused civilian deaths on countless occasions and repeatedly says the war on terrorism should not be fought—and cannot be won—in Afghan villages.

''An agreement has been reached clearly with Nato that no bombardment of civilian homes for any reason is allowed,'' Karzai said defiantly at a news conference at the presidential palace in Kabul on Tuesday.

''Even when they are under attack, they (coalition forces) cannot use an airplane to bomb Afghan homes,'' he said. To underscore his point, he repeated: ''Even when they are under attack.''

Air strikes on homes are a small part of international military operations in Afghanistan, yet they have brewed intense resentment among Afghans, who feel they employ a disproportionate use of force and put civilians at risk in their own homes.

The international force operates under a UN mandate, and while Afghan forces partner with coalition troops on night raids, coalition commanders are the ones who authorize air strikes.

Karzai said that at a meeting after the incident in Logar province, he asked US Marine Gen John Allen, the top commander of US and Nato forces in Afghanistan: ''Do you do this in the United States? There is police action every day in the United States. They don't call in airplanes to bomb the place.''

After the tragedy, Allen flew to Logar to apologize. The international military coalition says air strikes will be severely curtailed, designated now as a weapon of last resort to rescue soldiers.

On Tuesday, Nato said that Allen had issued an order telling US and coalition forces ''that no aerial munitions be delivered against civilian dwellings.

''But the statement also contained this caveat: ''As always, Afghan and coalition forces retain the inherent right to use aerial munitions in self-defense if no other options are available.''

At a Pentagon news conference on Tuesday, officials repeated the policy outlined by Allen but denied it differed greatly from Karzai's.

''We never remove from our troops in the field the right of self-defense,'' Navy Capt John Kirby, a Defense Department spokesman, said. ''We would never do that. And they still have the right to self-defense.''

US Marine Lt Gen Curtis Scaparrotti, said the new rules will not mean a large change for troops overall. Of the more than 1,300 cases in which air support was called in since January, 32 damaged civilian compounds and five civilian casualties were confirmed, according to the Pentagon.

''So the point I'm making is most of our ... engagements are engagements with the enemy that are not in compounds,'' he told Pentagon reporters in a video-conference from Afghanistan on Monday.

Scaparrotti on Tuesday handed over his job—head of the coalition's joint command and deputy commanding general of US Forces in Afghanistan—to US Army Lt Gen James Terry at a ceremony in Kabul.

Also Tuesday, explosions in north and central Afghanistan killed seven people as insurgents worked to undermine the country's weak government by stepping up attacks.

Security forces appeared to be the targets in at least one of the attacks, but as frequently happens in the Afghan war, the dead were civilians.

A suicide bomber on a bicycle detonated his explosives, killing two civilians and wounding five Afghan policemen. The Ministry of Interior said a small child was among those killed at a bazaar in Chahar Bolak district.

Five other civilians died when their minibus hit a roadside bomb in Wardak province in central Afghanistan. Provincial spokesman Shahidullah Shahid said a three-year-old child was among those killed in Sayd Abad district.

The UN said last year was the deadliest on record for civilians in the Afghan war, with 3,021 killed. The number of Afghan civilians killed dropped 36 per cent in the first four months of this year compared with last year, but the UN complains that too many civilians are still being caught up in violence.

Anti-government forces, including the Taliban and other militants, were responsible for 79 per cent of civilian casualties in the first four months of this year, the UN said. Afghan and foreign forces were responsible for nine per cent. It was unclear who was to blame for the remaining 12 per cent.

In the south, a Nato service member was killed in a roadside bomb attack, the coalition said. No other information was disclosed. So far this year, 191 Nato service members have been killed in Afghanistan, including more than 130 Americans.