Attorneys for Wal-Mart briefed the committee earlier on Monday about the company's anti-corruption compliance program, the person said.

But Wal-Mart has not committed to briefing the panel on the substantive allegations raised by a New York Times report, a key request of the committee, said the staffer, who spoke on the condition of anonymity.

A Wal-Mart spokesman did not immediately respond to a request for comment. The company has previously declined to discuss the allegations citing pending investigations.

It is unclear what avenue the lawmakers could pursue if Wal-Mart declines to provide further information, since the Democrats do not control the House and no parallel investigation appears to be underway in the Senate. But the scrutiny further prolongs the spotlight on Wal-Mart and the scandal over its rapid expansion in Mexico.

Representatives Elijah Cummings and Henry Waxman, both Democrats, opened their inquiry after the New York Times reported last month that Wal-Mart had paid millions of dollars in bribes to facilitate that expansion, and that senior executives suppressed an internal investigation into the matter.

Last week the pair wrote to Wal-Mart chief executive Michael Duke and asked him to authorize the former general counsel of Wal-Mart International to cooperate in their probe.

Cummings, who is the ranking member of the House Oversight Committee, and Waxman, who is the ranking member of the House Committee on Energy and Commerce, last month also asked two lobbying groups about Wal-Mart's involvement in a campaign to amend an anti-foreign bribery law.

The Chamber of Commerce and the Retail Industry Leaders Association have participated in efforts to scale back the Foreign Corrupt Practices Act, a 1970s law that bars bribes to officials of foreign governments. Wal-Mart executives serve as directors at both groups.