The Standard & Poor's 500 index was on track for a seventh straight week of gains.
At midday Friday the Dow Jones industrial average was up two points at 13,975. The S&P slipped half a point to 1,520. The Nasdaq composite also lost half a point to 3,198.
Currency policy is high on the agenda at the meeting of the Group of 20 finance ministers. Japan's currency will be of particular interest because the country has been forcing the yen's value lower.
Energy stocks fell as the price of crude oil dropped nearly 2 percent to $95.52 a barrel.