Scotland’s energy minister has warned MSPs not to “indulge in theories about political configuration” after the Conservatives claimed that a possible stay of execution for the country’s only oil refinery had come about after the Greens were removed from government.

Màiri McAllan, the Cabinet Secretary for Wellbeing Economy, Net Zero and Energy, also declined to confirm The Herald’s report that a key component at Grangemouth had been brought back into action.

She said this information was an operational matter and commercially sensitive.

READ MORE: Doomed Grangemouth refinery set for stay of execution as unit restarts

Grangemouth is due to close next year, but on Tuesday we revealed that the hydrocracker, which produces jet fuel, diesel and Liquefied Petroleum Gas, had been started up again.

The decision to take it offline in April last year was seen as one of the key reasons why the the Petroineos owned refinery was due to close, as the cost of repairing the unit would be around £30m.

Insiders told us that the firm is now taking a "watch-and-see" approach and that this may mean closure could be delayed until nearer to 2027, as this is when new investment on the hydrocracker will be vital.

Tory MSP for Central Scotland, Stephen Kerr, raised The Herald’s report in Parliament.

He asked Ms McAllan to confirm that the hydrocracker had been restarted.

“What impact does the return to sustained profitability mean for extending the life of the refinery?” he added.

The Herald:

The minister said this was “purely an operational matter for the company, and it is commercially sensitive".

She added: “It is not appropriate for me to speculate or theorise on what is, in essence, media speculation at this point, but I can assure Stephen Kerr and members that ministers and officials engage regularly with all those with an interest in the cluster, including with the business, to understand the impact of current operations.

“We are interested in operations today and how that progresses into the future.”

Mr Kerr said it was “a matter of interest for her and her team to find out whether the hydrocracker has been restarted".

“We have it from multiple sources that it has been, and that is a significant development,” he added.

The Tory suggested that “the window of opportunity that the restarting of the hydrocracker brings” was “not unrelated” to Humza Yousaf’s decision to scrap the Bute house agreement and sack the two Scottish Greens ministers.

READ MORE: How Scotland's 'black gold' made Grangemouth's closing refinery iconic

Ms McAllan replied: “Given the importance that Stephen Kerr places on the matter—as I do—I encourage him not to indulge in theories about political configuration on the one hand and, on the other, what are, in essence, commercial matters for Petroineos to consider.

“I restate the fact that it is not appropriate for me to comment on media speculation, but I reinforce the point that ministers and officials are very closely engaged in the development of these matters.”

Labour’s Sarah Boyack asked the minister for an update on the promised just transition plan for Grangemouth.

Ms McAllan promised it would “be published very soon".