Finance Minister Taro Aso has pushed back against U.S. efforts to bring yen policy into scope for bilateral talks aimed at striking a trade deal.

"We can't agree to any talk of linking currency and trade policy," Taro Aso told reporters Thursday in Washington after he met with U.S. Treasury Secretary Steven Mnuchin.

This was the first time Mnuchin had spoken directly with Aso about currency in the context of trade, according to a Finance Ministry official who briefed reporters. The official said he believes that talks concerning currencies will be secondary to the trade talks between economy minister Toshimitsu Motegi and U.S. Trade Representative Robert Lighthizer that kicked off last week.