The EU has said Morocco's occupation of a tiny island it disputes with Spain could imperil EU-Moroccan ties and urged a quick solution.
Spain has sent gunboats to protect territory it controls along Morocco's coast. It has demanded that Rabat withdraw troops from the tiny disputed island of Perejil, close to the Spanish enclave of Ceuta on Morocco's north coast.
The European Commission said Mr Chris Patten, the EU Commissioner for External Relations, had expressed grave concern to the Moroccan ambassador over the incident.
"He said that if this problem was not quickly resolved, it was likely to have damaging implications for EU-Morocco relations," the Commission said in a statement.
"The EU therefore hoped that intensive efforts would be maintained over this weekend to resolve the problem." The EU co-operates with Morocco under the so-called Euro-Mediterranean Association Agreement, which provides for regular political consultations, gradual trade liberalisation and joint action against illegal immigrants who infiltrate Europe from northern Africa.
Moroccan soldiers landed on Perejil island, just off the Moroccan coast, on Thursday. The islet has belonged to Spain since the 17th century, but is claimed by Morocco.
Spain sent troop reinforcements to islands it claims near Morocco yesterday, saying Rabat's dispatch of a dozen soldiers to a tiny disputed islet there was an "unfriendly act". Madrid said it had issued a formal protest to Rabat and was strengthening its military presence on the islands off its North African enclaves of Ceuta and Melilla.
Madrid said further Moroccan troop movements were observed yesterday around Spain's Chafarinas Islands.
Morocco has rejected Spanish demands that it withdraw its troops from Perejil, a rocky outcrop only 200 metres from its coast. A Moroccan official said the troops had "every right" to be there. He argued that Perejil had been under Moroccan sovereignty since it was "liberated" in 1956, when the Spanish protectorate over Morocco came to an end.
The decision to set up an observation post there was "neither a provocation or a threat towards Spain", he said.