By Peter Blackburn

BRUSSELS, Aug 19 (Reuter) - The European Union and Morocco agreed on Saturday to take a six-day break in marathon fisheries negotiations while they consulted their capitals on how to end the deadlock.

The EU and Morocco had tried unsuccessfully for the past nine days to narrow differences over the level of EU fish catches in Moroccan waters, the main obstacle to a new three-year accord.

"Both sides agreed a pause so as to proceed with necessary consultations," a European Commission spokeswoman said, quoting a joint press release. "They also agreed to continue the sixth round of negotiations on August 25.".

EU Fisheries Commissioner Emma Bonino told a news conference earlier that a deal was unlikely before a September 1 deadline set by the EU. "Theoretically it's possible but it seems to me unlikely," she said.

A new agreement is especially important for Spain, where about 650 fishing vessels have been confined to port since the end of April when Morocco scrapped a previous accord.

A failure to renew the agreement, the E s most important external fisheries pact, could spark violent protests in southern Spain, the Canary Islands and Portugal.

Bonino said the two sides were still far apart on quotas, adding that several telephone calls to Moroccan Fisheries Minister Mustapha Sahel had failed to break the deadlock.

Moroccan demands for quota cuts of up to 65 percent were unacceptable for economic and biological reasons, she said.

"Everyone knows there will be a reduction...but the level demanded by Morocco would mean there would no longer be any point in having an agreement," she said.

The two sides also disagreed on how to proceed. The EU wanted to start drafting a text covering areas where there was a consensus, such as fisheries controls, leaving points of disagreement, notably fish catches, blank.

"It would make it easier at the end to analyse the differences and enable a political compromise," Bonino said. If things were left vague it could take weeks to draft a text after reaching agreement, she said.

But Morocco disagreed, saying that drafting a text should start only after there was an overall agreement.