AP source: US to try to block Halliburton from buying rival

The $35 billion deal would combine two of the world's three leading providers of oilfield services to oil and gas companies and create a bigger rival to the industry leader, Schlumberger Ltd.

Few, however, predicted the depth and duration of lower prices caused by a global oversupply of oil.

Halliburton shares rose 40 cents to close at $34.40, while Baker Hughes shares fell $2.11, or 5.1 percent, to $39.36.

Since the last trading day before their deal was announced, Halliburton shares have lost 38 percent and Baker Hughes stock has fallen 34 percent.