NSW Energy Minister Chris Hartcher has described his resignation from state cabinet amid a corruption investigation as "appropriate" but remains confident he will be "cleared of any wrongdoing".
In a statement, Mr Hartcher said the issue of a search warrant against him was the first contact he had with the corruption watchdog but that "given their investigations have this far had an unknown timeframe", it was appropriate that he relinquish his ministerial portfolio.
He confirmed he would hold his seat as Terrigal MP pending the outcome of the ICAC probe and said it would not be appropriate to comment further.
NSW Premier Barry O'Farrell accepted the resignation and announced Fair Trading Minister Anthony Roberts would act as Minister for Energy and Resources in the interim.
The search warrant is believed to be linked to a Fairfax media investigation, which last year revealed that two of Mr Hartcher's staff members were involved in a political donations scandal in the lead up to the 2011 state election.
The ICAC has not confirmed whether Mr Hartcher himself is under investigation.
His rivals were quick to condemn yet another NSW resources minister for drawing the attention of the ICAC.
NSW Greens MP John Kaye suggested Mr Hartcher had been "caught in the web" of campaign donation irregularities, a sin which Mr O'Farrell has promised to stamp out in State Government ranks.
Anti-coal seam gas activists hoped Mr Hartcher's resignation would give more weight to their calls for a broad-ranging inquiry into mining in NSW.
Carmel Flint, campaign co-ordinator for the Lock the Gate Alliance, said corrupt conduct findings against former NSW Resources Minister Ian MacDonald and former Labor powerbroker Eddie Obeid had already caused the community to lose all faith in the integrity of those controlling the mining industry and "we can no longer allow the shadow of corruption to cloud decision-making".
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