By Zeke Turner and Tom Fairless 

BERLIN--German Vice Chancellor Sigmar Gabriel warned on Sunday that negotiations to build a vast trans-Atlantic free-trade zone have failed, amid mounting criticism of the deal, particularly in Germany and France.

"From where I'm sitting, the negotiations with the Americans have failed. Just nobody says that," said Mr. Gabriel, who has represented Germany in the talks, during an appearance at the German government's open house.

Brussels and Washington have been rushing to complete the negotiations by the end of this year, but members of Mr. Gabriel's center-left party spoke out last month to say they were dead in the water. France's Prime Minister Manuel Valls warned earlier this year that the deal would serve as "a breeding ground for populism."

German Chancellor Angela Merkel, a full-throated advocate of the deal from the start, has said she would like the negotiations to be completed before Germany's federal elections next year.

Meanwhile the deal has been rapidly losing popularity with the German public. In May, public broadcaster ARD's DeutschlandTrend survey showed that 70% of Germans opposed the deal, a 15-point increase since 2014.

Write to Tom Fairless at tom.fairless@wsj.com

(END) Dow Jones Newswires

August 28, 2016 12:04 ET (16:04 GMT)