In a December 17 email to staff filed in regulatory documents, Lesar stressed that the Baker Hughes deal was "not an acquisition to become more profitable through cutting costs - although we will need to eliminate duplications and achieve synergies to be an effective customer-focused organisation".

Halliburton confirmed earlier this month that about 1000 employees from its eastern hemisphere operations would be cut, effective immediately, which it said was necessary to "work through this market environment".

In his most recent communique, Lesar said on December 17 that the Baker Hughes acquisition would not render the company immune to market conditions and "right now it looks like 2015 is going to be a tough year".

"We will have to make reductions to our structure as any prudent business would. But I want to be clear — these reductions are related to market conditions, not the acquisition," the CEO said.

"It's important to remember that distinction as we go forward."

Lesar acknowledged workforce uncertainty over the acquisition, but promised them honesty and forthrightness as the future unfolds pre and post-acquisition, as he will lead the new merged entity.

"I know you have questions about the road ahead," he said.

"The integration team and I will give you as much information as promptly as possible," he said. "We remain committed to providing you with the most open and transparent communication.

"This acquisition will allow us an even bigger platform that will benefit both sets of employees. Just think for a moment about the career opportunities available in an organisation with over 120,000 employees, including the more than 1000 ex-Baker Hughes employees in our Halliburton family now."

He said Halliburton would follow the same business model that successfully brought it to the point where it could acquire Baker Hughes.

"Our strategies have served us well and I have no intention of changing them," Lesar said.

"Our focus on leading in unconventional resource development, outperforming in the deep water complex and rapidly growing our mature field business has worked very well and will continue.

"Many of our business lines will be significantly strengthened with the addition of the Baker Hughes people, technology and customer relationships.

"This acquisition will help us grow our revenues, expand our footprint, add high quality resources, spend more on select technologies and compete more effectively in underserved markets around the globe.

"This is not an acquisition to become more profitable through cutting costs, although we will need to eliminate duplications and achieve synergies to be an effective customer-focused organisation."

Lesar said the two companies would continue to operate independently until the Baker Hughes acquisition closes in the second half of 2015.