The tender closed on Friday but no purchase has yet been made as offers were still being considered, they said.
Eight offers were presented but three of them did not meet the full tender requirement or were not clear, they said.
Ethiopia is struggling with the impact of a drought last year that devastated farms in some regions. The country has a large wheat import programme but reportedly failed to agree a purchase in its last wheat tender in April because of contractual disagreements.
The lowest offer of $251.30 was made for 100,000 tonnes by Promissing International, including credit financing and carriage by seller vessel.
The same trading house also made the lowest offer for another 100,000 tonnes at $254.80 C&F, also including credit financing and carriage by seller vessel.
The second best offer was made at $264 and $270 a tonne C&F.
The wheat tender was seeking shipment two months after contract signing.