WASHINGTON, Dec. 15 (Xinhua) -- The United States, Ukraine and Europe have reached consensus or significantly closed gaps on 90 percent of their differences on a 20-point draft peace plan, reports said on Monday, citing two senior U.S. officials.

The comments came after U.S. President Donald Trump's special envoy Steve Witkoff and son-in-law Jared Kushner met with senior Ukrainian and European officials in Berlin over the peace deal on Sunday and Monday.

Ukrainian President Volodymyr Zelensky said in a post on social media platform X that the Berlin talks were a "first draft," warning of "destructive" elements to be removed.

Zelensky said Ukraine has compromised by accepting strong security guarantees instead of NATO membership, though it remains unclear what type of U.S. commitments on Ukraine's security guarantees would entail and whether the U.S. Senate will be required to ratify any Article Five-like arrangements for a non-NATO country.

NATO's Article Five calls on allies to assist any member that comes under attack.

Meanwhile, the issue of territorial concessions remains a sticking point. Zelensky has said it would be impossible for Ukraine to give up territory, mostly in Donetsk, that Russia has not taken on the battlefield.

Trump said Monday that he believed an end to the Russia-Ukraine conflict is closer than ever, warning the talks remain "difficult."

"I think we're closer now than we have been, ever, and we'll see what we can do," Trump told reporters at an event in the White House. "Things are seemingly going well, but we've been saying that for a long time, and it's a difficult one."

Asked if there will be an Article Five-like deal without NATO membership for Ukraine in the emerging peace plan, Trump said, "In terms of security guarantees, we're working with Europe on it. Europe would be a big part of that, so the war doesn't start up again."

Negotiators are planning to meet in the United States this weekend, a U.S. official said during a phone briefing to the media. Enditem