Oil services giant Halliburton is facing more questioning from the US Justice Department over the potential acquisition of rival Baker Hughes, reported the Houston Chronicle.

According to the report, the US government has anti-trust concerns over what will happen if the world’s second and third largest service companies merge. Halliburton confirmed that the company is cooperating with the second round of questioning, saying that it expects the merger to be completed by December 1st, a more concrete timeline than previously announced.

If the deal falls through, Halliburton is obligated to pay Baker Hughes $3.5b. Both companies have recently been cutting costs ahead of the merger’s completion, with Halliburton laying off around 14,000, and Baker Hughes another 13,000.

Reuters revealed that the companies are also under scrutiny from the European Commission, which is looking into the merger in “a few discrete areas.” Combined, the two companies will become larger than the current largest oil services provider, Schlumberger.