DOLLAR SLIP

The dollar was down slightly against the yen at 109.38 yen, back near the day's low plumbed after Trump told supporters in Arizona "If we have to close down our government, we're building that wall".

The greenback remained clear of a four-month low of 108.605 yen plumbed last week, when turmoil in the White House and geopolitical tensions took a toll on the currency. 

The dollar index against a basket of six major currencies was down slightly at 93.412 after rising 0.5 percent the previous day. 

Trump's suggestion the NAFTA trade treaty could be scrapped to jumpstart ongoing renegotiations also sent Mexico's peso down 0.6 percent against the dollar. 

The euro was up 0.2 percent at $1.1784 after slipping about 0.5 percent Tuesday on weaker-than-expected German investor confidence. 

Speeches from European Central Bank President Mario Draghi and Fed Chair Janet Yellen will headline the annual Jackson Hole event, although neither are expected to announce any significant policy. 

Draghi gave a speech at Lindau, Germany, on Wednesday but did not discuss the ECB's current monetary policy. 

In commodities, Brent crude traded 0.3 percent lower at $51.68 a barrel after data showed a surprise build in U.S. gasoline inventories. Improving Libyan output also added to oversupply concerns in the crude oil market.

Nickel prices rose to an eight-month high while zinc touched its highest since August 2007 on expectations of strong demand from China, supply concerns and declining stockpiles. 

Benchmark zinc was up 0.8 percent at $3,142.50 a tonne after rising to $3,231.75, its highest since August 2007. Zinc has risen on expectations of a large global deficit and a sharp fall in stocks.

Spot gold was a shade higher at $1,287.58 an ounce, after losing 0.5 percent overnight as the precious metal felt the pressure from a stronger dollar. Spot gold had reached a nine-month high above $1,300.00 an ounce on Friday.