March 4 (Reuters) - U.S. Secretary of State Marco Rubio spoke with Saudi Foreign Minister Prince Faisal bin Farhan on Wednesday and discussed the threats from Iran to regional stability and other developments in the region, the U.S. State Department said."The Secretary expressed gratitude to the Foreign Minister for Saudi Arabia's response to the attack on U.S. Embassy Riyadh," State Department spokesperson Tommy Pigott said in a statement.