Updated

More international groups are calling Nigeria's National Assembly election largely transparent and fair ahead of the oil-rich nation's coming presidential vote.

The Commonwealth Observer Group issued a statement Monday saying Saturday's vote "generally took place in a peaceful and orderly manner." The top U.S. diplomat for Africa, Johnnie Carson, said Monday that the election represented "an important achievement for Nigerian democracy."

Both Carson and the Commonwealth group noted the logistical challenges still facing Nigeria's Independent National Electoral Commission and the dangers of communal violence.

Nigeria will hold its presidential election this coming Saturday. It will hold gubernatorial elections April 26.