"If I was head of the ESOT, " said O'Brien, "they should just go and buy three or four percent this morning and it's all over."

He said both airlines were complimentary products.

"The two companies are valuable to the economy, " O'Brien said. "For inward tourism and also for people going out to create new markets for Irish businesses.

They should be separate."

While advisers to Ryanair, Aer Lingus, the ESOT and the government bunkered down in separate camps this weekend for a bruising takeover battle that may last weeks, there were indications that Aer Lingus union members were taking O'Brien's suggestion seriously.

A senior union source in Aer Lingus said that the ESOT would be "very foolish" if it didn't consider increasing its current 12% stake in Aer Lingus in an effort to head off O'Leary's audacious bid.

But the union source ruled out approaching the Government for a loan to buy the extra shares needed to lift the workers' share closer to Ryanair's stake of almost 20%.

"The 12% workers' stake is worth around 200m and the Trust would have few problems using this as collateral to raise a loan of 100m which it could then use to buy a further 6%, raising its stake to 18%, " said the source.

"If a banker can be found who would be willing to lend us that type of money on a commercial basis, then the Trust would be mad not to consider it, " said the union source.

But he added that while the security for such a loan would not be a problem, repayments might be. It could, for example, be an interest-only loan. "The nuts and bolts would need to be worked out, but it is more than possible, " he said.

With regard to a 'white knight' coming to the aid of the workers who fear Ryanair's anti-union stance, the senior union source said that if one was arrive on the doorstep, "we wouldn't be beating it away with a stick".

Market rumours swirled this weekend that an Irish entrepreneur, rather than an airline such as BA or Emirates, might be trying to accumulate a blocking stake in Aer Lingus.

However, he conceded that while Irish investors' names such as Denis O'Brien, Sean Quinn, Tony O'Reilly and others had been bandied about, at the week-end "nobody had put their head above the parapet".

Late Friday transport minister Martin Cullen reiterated the government's commitment to retaining a greater than 25% share in the airline and maintained a takeover would not deliver benefits to Irish consumers.

In response, Ryanair restated their promise to reduce Aer Lingus fares by 10% over four years and maintained that 2.80 was their best offer. Analysts said the company would likely be forced to make an improved bid in the coming days.

Some observers noted that O'Brien's comments, made to selected reporters following a business breakfast on Friday hosted by Vision consulting, followed a Ryanair advertising campaign promoting "free" flights to Malta that included a picture of O'Brien and the tagline, "All You Pay is Taxes".