(Updates with EU trade chief)
VIENNA/BRUSSELS, Sept 21 (Reuters) - Canada's trade minister and the EU trade chief sought on Wednesday to overcome the doubts of Austria and other EU members over a planned EU-Canada free trade deal, with a declaration spelling out the limits of the contentious pact.
Canadian Trade Minister Chrystia Freeland, speaking in Vienna, said the legally binding additional declaration on key issues would add no new elements to the deal, which Austria's chancellor opposes in its current form.
"What the joint declaration can do is strengthen elements which already exist in the agreement," Freeland told a joint news conference with Austria's Economy Minister Reinhold Mitterlehner on Wednesday. "What it is not able to do is introduce entirely new elements."
The Comprehensive Economic and Trade Agreement (CETA) has been a key target of protests by unions and environmental and other groups who say it will worsen labour conditions and allow big business to challenge governments across Europe. L8N1BW3TG
European Trade Commissioner Cecelia Malmstrom wrote in a letter to Mitterlehner, published on Wednesday, that the aim of the declaration was to dispel concerns by spelling out what was in CETA.
"We intend to clarify all the points that have sparked particular concern in public debate, especially the ability of governments to provide public services and the protection of labour and environmental standards," she wrote.
CETA, and a planned EU-U.S. trade deal, will be the focus of a meeting of trade ministers in Slovakia on Friday.
The EU-Canada deal could enter into force next year if member states and the European Parliament approve it. The chances of that happening rose on Monday after the German Social Democrats, junior partners in the ruling coalition, gave their backing. Austria, Belgium, Bulgaria, Hungary, Romania and Slovenia still have reservations.
Mitterlehner, a conservative who supports CETA, unlike social democrat Chancellor Christian Kern, said it might take a few weeks for the government to find a common line ahead. European affairs ministers are expected to vote on the deal on Oct. 18 before a planned signing at an EU-Canada summit on Oct. 27.