Spanish Defence Minister Jose Bono has said comments by a general suggesting military intervention in Catalonia are not supported by the armed forces.
Lt Gen Jose Mena Aguado said the words were all his own
Lieutenant-General Jose Mena Aguado was put under house arrest after saying the army could be deployed if autonomy plans violated the constitution.
Mr Bono is also expected to recommend the general's dismissal as head of the army's ground forces.
A statute on more autonomy for Catalonia is being debated by MPs.
A first reading of the plan, which included giving the affluent region rights to control taxation and change laws passed by parliament, was approved by 197 votes to 146 by the Spanish parliament in November.
But it still has to be amended to comply with Spain's constitution. The issue has divided the ruling Socialist Party and infuriated conservatives, who say it will cause Spain to break up.
Lt Gen Mena told an audience of military officers on Friday that the army would have a constitutional right to intervene if Catalonia received too much self-government.
His comments triggered a swift response from the government - it placed him under an eight-day house arrest - and may have reminded Spaniards of their troubled past.
The Civil War was followed by four decades of military rule under General Francisco Franco, until his death in 1975.
The fledgling democracy that followed was threatened by a coup attempt led by Colonel Antonio Tejero on 23 February 1981 - resolved only by the intervention of King Juan Carlos.
On Monday, Mr Bono appeared on Spanish radio and television reassuring people that Lt Gen Mena's comments were down to a "one-off piece of indiscipline".
He told radio Cadena Ser that democracy had to emanate "from the ballot box and not the barracks".
The general's comments breached the political neutrality required of all members of the military, he told Canal 24 Horas television.
"The military, like lawyers, priests and building workers, have political views," he said. "But there are limitations that they accepted when they swore their oath and accepted membership of the military."
Mr Bono added that the general had told him categorically that he had written the speech on his own and "that nobody had induced him to say what he said".