GM's chairman has warned that pay restrictions for executives set by the US government could impair attempts to hire externally.

Ed Whitacre, who became chairman of a reconstituted 13- member GM board when GM emerged from Chapter 11, said GM would face difficulties in hiring senior executives from outside the company under the current pay caps set by the Obama administration.

Under the caps set for GM's top 25 executives, GM Chief Executive Fritz Henderson had his cash salary cut 25 percent to US$950,000 from US$1.26m, Reuters reported.

The report added that cash salaries for the top executives were cut by 31 percent and only one other unnamed executive other than Henderson will be paid more than US$500,000 for 2009.

Whitacre said that $500,000 limit made hiring from outside difficult and urged a reconsideration of the limits.

"To find top-level people where you need them, that's a more difficult thing to do at that salary level," Whitacre told reporters.