RNA - Altmaier said on Monday Berlin "at this stage will not approve further arms exports because we want to know what happened," adding that all explanations so far have been unsatisfactory.
He echoed earlier remarks by Chancellor Angela Merkel who vowed to suspend arms exports to Riyadh until uncertainty over the fate of Khashoggi vanishes.
"When it comes to our already limited arms exports ... they cannot take place in the current situation," she said at a news conference on Sunday.
But Altmaier, a close Merkel confidant, emphasized that "there won't be any positive effects if only we halt exports and then other countries fill the gap."
"Only when all European nations are in agreement will this make an impression on Riyadh," he said, speaking on public broadcaster ARD.
Last month, Germany approved 416 million euros ($480 million) worth of arms sales to Saudi Arabia for 2018, going back on a ban that the European country had ordered on the sale of weapons to the countries involved in the war on Yemen.
According to Press TV, Germany, one of the world's biggest arms exporters, had ordered the ban on the weapons delivery in March in an apparent reaction to the Saudi invasion of Yemen.
The case has opened a serious new rift with Britain, France and Germany which are urging Saudi Arabia to provide "credible" facts for its explanation about the killing of Khashoggi.
French President Emmanuel Macron spoke to US President Donald Trump on Khashoggi's death on Monday.
Trump on Sunday delivered his strongest comments yet about the affair in an interview with The Washington Post, saying, "Obviously, there's been deception and there's been lies."
Saudi Arabia on Saturday admitted that the critic had died in its consulate in Istanbul after "discussions" turned into "a brawl and a fist fight." It followed Saudi Arabia's denial for two weeks of its role in Khashoggi's disappearance.
Khashoggi was a Washington Post columnist and lived in the US, having fled Saudi Arabia last September.
The kingdom’s explanation on Khashoggi’s death has been met with skepticism with world powers demanding answers and the whereabouts of his body.