Defense ministers in Kabul

As de Maiziere arrived on Wednesday in Afghanistan, there was a major security alert surrounding the arrival of his US counterpart Leon Panetta.

A vehicle was driven onto the runway of Camp Bastion, the main British base in southern Afghanistan, and burst into flames at about the same time Panetta landed there.

"At no point was the secretary or anyone on the aircraft in any danger from this incident," the International Security Assistance Force (ISAF) said in a statement, adding that "the alleged perpetrator" had been detained. He was reportedly an Afghan man who had stolen the truck for unclear motives. After crashing the truck he emerged from the vehicle on fire, and was reportedly being treated for burns.

The defense minister visits came at a tense time between Afghanistan and the international community. On Tuesday, gunmen shot at a delegation of Afghan officials during a service for 16 civilians, mainly women and children, reportedly killed by a US soldier in a shooting spree in Kandahar province. The soldier accused of the civilian massacre was flown out of Afghanistan on Wednesday, according to the Pentagon.

The visits by de Maiziere and Panetta had been scheduled before the massacre. During his visit to the south of the country, Panetta told troops the Kandahar massacre should not sway them from their task of securing the country ahead of the planned withdrawal.

The American attacker was identified as a 38-year-old father of two based in Washington state who served three tours in Iraq. The Pentagon is withholding his name.

Withdrawal 'on track'

In Kabul, de Maiziere met Afghan counterpart Rahim Wardak and President Hamid Karzai. He said plans to withdraw NATO troops from Afghanistan by 2014 were on track.

US President Barack Obama echoed that sentiment in Washington, hosting British Prime Minister David Cameron. Obama said the two country's forces were "making very real progress" in Afghanistan.

German Chancellor Angela Merkel had caused confusion with comments she made on Monday in Mazar-e-Sharif in which she said that progress had been made toward political reconciliation with insurgents - but that it had not gone far enough.

"That's why I cannot yet say that we will manage it by 2013-2014," she said.

The defense ministers' trips to Kabul come ahead of a NATO summit in May, at which countries contributing to the international mission in Afghanistan are expected to map out the post-withdrawal period.

ncy,rc/slk (AP,dpa, AFP)