The pan-European STOXX 600 index ended 0.3% lower after gaining 2.5% over the last five sessions. Defensive plays including healthcare and utilities <.SX6P> were the only sectors to rise, suggesting appetite for risk remained muted.
Trump's comments worsened sentiment already hit by a similar statement from White House trade adviser Peter Navarro as well as sources who said the plan faced fierce internal opposition at the White House.
That ended days of optimism as officials said tariffs would be rolled back and the deal would be signed soon, which along with an earnings season that has proved less weak than expected, helped STOXX 600 log its firth straight week of gains.
"This sentiment that perhaps investors should look to fade the optimistic advance that you saw in the earlier part of the week has been in the markets for about a day and a half," said Ken Odeluga, market analyst at City Index.
"The comment from the White House in more recent hours are merely conformation of that. The fact that Donald Trump has actually echoed some of these comments is a reason to adopt a defensive position into the weekend."
Miners, among the most exposed to the trade conflict and its implications on global growth, dropped 1.6%.
Bank stocks <.SX7P>, slid 1.2%, hit by declines for some of France's biggest lenders. Shares in Credit Agricole fell 2.3% as quarterly numbers in its corporate centre and retail arms came in below analysts' expectations.
Shares in Natixis fell 7.3% after it trimmed its budget for potential acquisitions to focus on reinforcing existing businesses.
Richemont slumped 5.7% after the luxury goods group said political protests in Hong Kong weighed on sales growth in the six months to Sept. 30.
In bright spots, Telecom Italia rose 1.2% after the company said it had made progress in cutting its debt burden, while London-based insurer Beazley topped the index as falling U.S. yields boosted investment returns, helping it fare better in comparison to larger rival Hiscox.
Over the weekend, Sunday's parliamentary election in Spain, the fourth in four years, will be closely watched. According to a calculation by El Pais newspaper based on dozens of opinion polls the election will do little to break a long-standing stalemate.
New parties have emerged after a financial crisis, fragmenting the political landscape and making it much harder to form governments with stable majorities.
Madrid's benchmark stock index closed 0.6% lower, logging its worst day in a week and a half.
Italian shares bucked the trend to end 0.1% higher, lifted by shares of Enel which rose after a UBS target price hike. The utility firm was awarded all 9,600 MW it offered in Italy's first capacity market auction, the Italian power group said on Friday.
By Susan Mathew