(Adds spokesman, background)
OSLO, June 6 (Reuters) - Aluminium exports from the Qatalum metals plant have been blocked by top Arab nations breaking off diplomatic ties with Qatar and Norway's Norsk Hydro warned it would take time to restart them.
"Most Qatalum shipments normally go through the large Jebel Ali port in (the) UAE, but this port looks to be closed for all Qatar shipments from Tuesday morning," Norsk Hydro said in a statement on Tuesday.
Saudi Arabia, Egypt, the United Arab Emirates and Bahrain cut ties with Qatar on Monday, accusing it of support for Islamist militants and Iran.
Qatar denounced the action as predicated on lies about it supporting militants. It has often been accused of being a funding source for Islamists, as has Saudi Arabia.
Norsk Hydro has a 50-percent stake in the Qatalum joint venture, which produces more than 600,000 tonnes of primary aluminium per year. This is exported to customers in Asia, Europe and the United States.
State-owned Qatar Petroleum owns the other half.
"Supported by owners Hydro and Qatar Petroleum, the Qatalum JV is currently working to find alternative shipment routes to enable it to continue to serve its global customers," Norsk Hydro added.
A company spokesman said that any solution would take time. "There are several alternatives we are looking at and we will look at all possibilities," he said.
"But this is complex and will take some time." (Reporting by Terje Solsvik and Joachim Dagenborg; writing by Gwladys Fouche; editing by Alexander Smith)