By John ‌Irish and Louise Rasmussen

PARIS, Dec 12 (Reuters) - Ukraine, the United States and European powers are still ‍working to ‌find a joint position that would outline the contours of a peace deal, including security guarantees ⁠for Kyiv, that could be taken to ‌Russia, a French presidency official said on Friday.

"Our goal is to have a common foundation that is solid for negotiation. This common ground must unite Ukrainians, Americans and Europeans," the official told reporters in a briefing.

"It ⁠should allow us, together, to make a negotiating offer, a solid, lasting peace offer that respects international law and Ukraine’s ​sovereign interests, an offer that American negotiators are willing to bring ‌to the Russians."

The official said there was ⁠no joint document yet but all sides would carry on negotiations in the coming days through various calls and meetings. He did not say whether Washington had set a deadline.

Kyiv is ​under pressure from the White House to secure a quick peace but is pushing back on a U.S.-backed plan proposed last month that many see as favourable to Moscow.

Britain, France and Germany, along with other European partners and Ukraine, have been working frantically in the last few ​weeks to ‍refine the original U.S. proposals ​that envisaged Kyiv giving up swathes of its territory to Moscow, abandoning its ambition to join NATO and accepting limits on the size of its armed forces.

The French official said the talks were aimed at narrowing differences with the United States and centred on territory and potential security guarantees for Ukraine once there is a peace accord.

Those discussions include the possibility of a NATO Article ⁠5-type clause involving Washington that would seek to reassure Kyiv in case it was once again attacked by Russia, the official said.

The Europeans have ​also faced pressure in recent weeks with some American proposals touching on elements that concern NATO and the European Union, including suggestions on fast-tracking Ukraine's accession to the bloc.

"The European perspective of Ukraine is clear and it's a realistic perspective," the official ‌said. "That is what we are committed to and it is up to the Europeans and the Ukrainians to agree on how to proceed."

(Reporting by John Irish, editing by Louise Rasmussen and Hugh Lawson)