Concern that the European Commission could gain control of Britain’s North Sea oil resurfaced last night.

The threat came on the eve of vital talks in Brussels that will decide the draft text of the EU constitution.

Offshore oil industry sources joined the Foreign Office last night in denying that the energy chapter, as the section is known, which was ditched in May, posed any threat to British interests.

A caveat inserted into the text to meet the UK’s demands insists it will not affect Britain’s right to control its natural resources.

But Transport and Energy Commissioner Loyola de Palacio sent a clear signal of her hopes in an earlier speech in which she called for powers “to ensure a common and interdependent approach to the problems of security of supply for oil”.

Prime Minister Tony Blair has also been urged to ensure there is no prospect of anything in the chapter being used to undermine the UK’s position.

SNP Westminster leader Alex Salmond, who originally sounded the alarm over the oil-grab threat in a speech to the UK Offshore Operators Association, said: “The prime minister had better pay attention to de Palacio’s speech and realise that, although the text is still robust, the aim and ambition of the commission may cut across our vital interests in future.”

Aberdeen Central Labour MP Frank Doran sent an urgent message to Mr Blair in Brussels “to ensure he is aware of the importance of this issue to the North Sea oil industry”.

He said he was sure the prime minister would take care the safeguards written into the chapter were maintained and would not let anything slip by.

Gordon Liberal Democrat MP Malcolm Bruce said the Government must ensure the chapter did not mean the commission had any power to take control of British energy supplies.

He added: “It would be absurd to suggest the commission does not have a legitimate interest in ensuring security of energy supplies for the whole EU.

“As long as that falls short of taking control of individual members’ energy resources, that is satisfactory.”

UKOOA’s public-affairs manager for Europe, John Conmy, said his organisation was comfortable with the development.

“We support any draft text that clarifies the law by preserving the offshore policy status quo and it would appear that this new draft chapter does that sufficiently well,” he said.

A Foreign Office spokesman said officials had “crawled” over the wording to ensure there was no possibility of future eurocreep – the term used for the commission manipulating loopholes to extend its powers.

He said the chapter now clarified the limited scope of the commission’s powers.

The chapter is in a section of the treaty labelled non-contentious by the Irish presidency and is unlikely to be raised formally at the summit.

Its re-emergence illustrates the complexity of European negotiation procedures, under which “nothing is agreed until everything is agreed” – which means issues everyone regards as settled can re-emerge.

Meanwhile, Mr Salmond renewed his attack on the BBC for delaying showing its programme Gutted, a documentary about the plight of the Scottish fishing industry, until Wednesday night, too late to influence the European parliamentary elections.

He congratulated producers for an excellent documentary – and accused Mr Blair of having no intention of standing up for Scottish interests and leaving fishing way down his list of priorities.

The Government refused to object to a clause in the draft constitution giving the commission exclusive competence over fishing.

A Britain in Europe NOP poll yesterday suggested Scots are more favourably disposed towards the European Union than voters in the UK as a whole.

Some 39% of Scots are either definitely or probably going to vote yes in the referendum on the constitution, about which European leaders are haggling in Brussels, compared with just 31% across the UK, and 35% no, compared with 45% across the UK.