PORTUGUESE GRAIN AGENCY BAN TO REMAIN - EC SOURCES A ban by a Portuguese court on the state buying agency EPAC taking part in cereals import tenders open to private traders will remain unless it is reversed in Portugal or challenged in the European Court of Justice, European Commission sources said. They denied a statement yesterday by Portuguese Agriculture Minister Alvaro Barreto that the commission had accepted that EPAC should be eligible, saying it had taken no view in the matter. Under the terms of Portugal's accession to the European Community, a grain import monopoly held by EPAC is being reduced by 20 pct annually until all imports are liberalised in 1990. Lisbon's civil court decided in a preliminary ruling earlier this month that EPAC should not be allowed to take part, as it had done in the past, in tenders for the liberalised share of annual grain imports.