Mr O'Brien said nuclear power was a source of low-carbon electricity, reports the Times.
Commenting on SNP statements that pointed Labour indecision on the issue, he told the news provider: "[The SNP] have a hole in the air where they need a policy.
"It is time they addressed the substance of the argument rather than scoring petty political points."
He added that the Scottish executive should not turn its nose up at the high-value jobs the nuclear energy sector would create.
Meanwhile, the European Economic and Social Committee has called for greater transparency in the nuclear energy sector.
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