WASHINGTON (Reuters) - Negotiators working to revise a bill before Congress that would tighten scrutiny of foreign investment in order to limit Chinese efforts to acquire sophisticated U.S. technology are optimistic the measure will be signed into law by the end of the year, a senior U.S. Treasury official said on Thursday.

The bill in the Senate and a companion measure in the U.S. House of Representatives would broaden the reach of the inter-agency Committee on Foreign Investment in the United States (CFIUS), which currently looks at foreign acquisitions of U.S. companies or stock transactions that may hurt national security.

“I’m optimistic that it will be completed during this year if not by August,” the official said. The bipartisan legislation has the support of President Donald Trump’s administration.

CFIUS has gone from virtually unknown several years ago to front-page news this year as one of its probes resulted in President Donald Trump’s forbidding Singapore-based chipmaker Broadcom Inc from buying rival Qualcomm Inc.

Tightening the CFIUS process is one of several efforts supported by the Trump administration, including tariffs on steel and aluminum, to establish a more protectionist stance in an effort to tamp down Chinese imports while raising the regulatory bar on what deals get approved.

Negotiators in the administration, on Capitol Hill and working for the investment and high tech community are on their fourth version of a bill on CFIUS. The bill previously underwent at least one proposed revision that would seek to narrow its scope.

The initial draft of the bill could have expanded CFIUS oversight to anything sold by a “critical technology company,” a term meaning technology with military importance. Tech companies criticized that version on concerns that it would limit or slow their own exports. A revision trimmed the oversight language to “critical technology,” in hopes of preventing CFIUS from being flooded with applications related to older technology.