WASHINGTON (Reuters) - Lockheed Martin Corp <LMT.N> said it expects to close its $9 billion acquisition of Sikorsky Aircraft from United Technologies Corp <UTX.> on Friday, now that it has received final regulatory approval from China.

"With this final regulatory approval, we are one step closer to completing this historic acquisition," said Lockheed Chief Executive Marillyn Hewson.

United Tech told a Goldman Sachs investors' conference earlier on Tuesday that the Chinese approval had been received, and the deal should close by the end of the week.

Lockheed announced its planned acquisition of Black Hawk helicopter maker Sikorsky in July.

U.S. Senator Chris Murphy, a Connecticut Democrat, said the sale would be a win for Sikorsky employees and U.S. troops who relied on the company's helicopters.

Lockheed shares closed $1.69 or 0.77 percent lower at $218.90 on the New York Stock Exchange. United Tech's shares closed $0.61 or 0.61 percent higher at $100.

(Reporting by Andrea Shalal; Editing by Matthew Lewis and Phil Berlowitz)