The lowest offer apparently did not fulfil all tender conditions, which included a requirement to submit a second offer including inland transport costs to delivery points inside Ethiopia, they said.

The lowest offer fulfilling the tender conditions was $269.00 a tonne c&f to Ethiopian ports, they said.

The tender closed on Tuesday but no purchase has yet been made as offers were still being considered, 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 December because of contractual disagreements.

The new wheat tender seeks shipment two months after contract signing.

"The lowest offer of $250.15 was made for 100,000 tonnes but did not include the required additional offer for Ethiopian internal freight costs so there is suspicion it could be disqualified," one trader said.

The same trading house also made separate offers, all for 100,000 tonnes at $258.15, $260.75 and $261.95 all a tonne c&f, also without a second offer including Ethiopian freight.

The offer of $269.00 a tonne c&f was made separately by two multinational trading houses, both for 100,000 tonnes.

One made the second offer of $275.26 a tonne including Ethiopian freight costs and the other offered $275.58 including Ethiopian freight.

The wheat offered was thought likely to be sourced from the Black Sea region and possibly Pakistan if Pakistan can provide the required quality.