The drastic measure came shortly after United Kingdom revealed it had credible evidence of a security threat to its aviation interests.
“There is credible intelligence of a serious threat to UK aviation interests in Saudi Arabia,” a British government spokesman said.
The decision to suspend flights came about after consultations between the British Airways and the government.
Hastening the decision evidently was the disclosure that several suspects arrested in a shootout earlier this week in Saudi Arabia may have been plotting an attack against commercial aircraft at Riyadh airport.
The French news-agency, AFP quoted an unnamed US official as saying the Saudi authorities had discovered a document indicating the arrested persons had placed King Khalid International Airport under surveillance in preparation for a possible attack.
'There is credible intelligence of a serious threat to UK aviation interests in Saudi Arabia'
Police in Saudi Arabia claim to have arrested five terror-suspects on Tuesday after a shootout in al-Suwaidi residential district in southern Riyadh.
The official further said the US State Department was likely to issue a new travel warning for Saudi Arabia, warning of terrorist threats to commercial aviation.
The announcement of suspension triggered alarm in Saudi Arabia.
“It will send a very wrong message that Saudi Arabia is not a secure destination,” said a top columnist.
British Airways, which flies to the capital Riyadh and Red Sea port of Jeddah, is the only British carrier with scheduled flights to Saudi Arabia.
Flights to both destinations were cancelled on Wednesday.