* SPD leader says Kaeser should rethink decision to attend
* German foreign min says cancellations send right signal
* Kaeser has not made up his mind - Siemens spokesman
BERLIN, Oct 21 (Reuters) - Siemens boss Joe Kaeser came under pressure from senior German politicians on Sunday to pull out of an investment conference in Saudi Arabia next week following Saudi journalist Jamal Khashoggi's death.
Many business executives including the heads of Deutsche Bank, Uber Technologies and Siemens rival ABB have dropped out of Riyadh's Future Investment Initiative conference amid outrage about Khashoggi's fate.
The leader of the Social Democrats (SPD), Andrea Nahles, called on Kaeser to follow the example of other executives and cancel his plans to attend the conference.
"I hope that Joe Kaeser will rethink this," she told the Bild am Sonntag newspaper.
Foreign Minister Heiko Maas, also from the SPD, told German public television on Saturday evening that cancellations sent the right signal.
"I certainly wouldn't participate in an event in Riyadh at the moment," he said. "And I have great understanding for those who have cancelled."
Norbert Roettgen, a member of Chancellor Angela Merkel's Christian Democratic Union who chairs the German parliamentary foreign affairs committee, also urged Kaeser to skip the event.
"This applies in my view, for example, to the Siemens CEO who has confirmed his attendance," he told the Welt am Sonntag newspaper.
A spokesman for Siemens said Kaeser had not yet decided whether to attend the conference. He said he expected Kaeser to make a decision on Sunday.
The engineering conglomerate has won orders to supply gas turbines, power plant components and trains to Saudi Arabia. Last year, it signed a declaration of intent to work with Saudi authorities to equip infrastructure projects which Siemens said could be worth at least a billion euros.
Merkel and Maas have reacted strongly to Saudi Arabia's admission that Khashoggi died in the Saudi consulate in Istanbul, condemning the killing and demanding Riyadh make clear what happened.
$1 = 0.8686 euros Reporting by Caroline Copley; Editing by Dale Hudson