Halliburton Co said on Friday that it cut more than 6,000 jobs in the first quarter, during which revenue slumped 40.4 percent and it took a $2.1 billion restructuring charge mainly for asset write-offs and severance costs.

The No. 2 oilfield services provider also said it would now hold its earnings conference call on May 3, instead of April 25, to accommodate the April 30 deadline for its acquisition of Baker Hughes Inc.

Halliburton's "operational update" was issued in a statement after the market closed on Friday. The company is scheduled to report first-quarter results on Monday, April 25.

Halliburton and Baker Hughes have set a deadline of April 30 to close the deal, which will help close the gap on market leader Schlumberger Ltd. But, the merger, which was announced in 2014, faces stiff regulatory hurdles.

The U.S. Justice Department filed a lawsuit this month to block the deal, citing competition worries. European Union antitrust regulators could make its objections to the deal known to Halliburton next week, Reuters reported on Wednesday, citing sources.

The deal between the two companies was in part to help them weather the current oil price downturn, which started in 2014, and its aftermath. Since 2014, Halliburton has reduced its headcount by about a third and reduced costs drastically.

"Life has changed in the energy industry, especially in North America, and over the past several quarters we have taken the steps to adapt to that fact," Chief Executive Dave Lesar said.

The company said it expected spending on drilling and completion services to fall 50 percent in North America this year, following a 40 percent decline last year. It expects global spending to drop 30 percent for the second straight year.

Halliburton said its revenue dropped to $4.2 billion in the quarter ended March 31 from $7.05 billion a year earlier.