YES Scotland last night denied it was in meltdown after losing the last two members of its self-styled "top team" of directors.

The cross-party independence movement confirmed Ian Dommett and Stan Blackley had quit as director of marketing and deputy director of communities respectively, but insisted the organisation was in good shape. It is understood the exits were not voluntary.

The departures, which took place over the last 10 days, mean Yes Scotland has now lost all five members of what it called its top team since their appointment in September 2012. Yes camp insiders said such changes were common for a dynamic political campaign.

However, the pro-Union Better Together movement claimed Yes Scotland was "in crisis".

The changes come amid persistent rumours - always denied - that Yes Scotland is suffering from financial problems.

Last week, the Sunday Herald revealed Yes Scotland had decided to delay publication of its latest donor information, despite chief executive Blair Jenkins repeatedly promising financial transparency.

It has not revealed the source or scale of its funding since last April.

At the time of their appointment, Jenkins boasted in a press statement that his five directors were "a team of the highest calibre".

He said: "Each one of them has a proven track record in his or her field of expertise and I am confident that with their input and commitment we can deliver a Yes vote in 2014."

However, that plan rapidly fell apart, with insiders claiming Jenkins had miscalculated by hiring too many highly-paid managers.

Former RBS manager Jacqueline Caldwell left as director of operations in March last year for unexplained "personal reasons".

Former Glasgow University media boss Susan Stewart left as director of communications in July as part of a "streamlining" operation.

And former Nationalist MSP Shirley-Anne Somerville quit as director of communities in November.

Now Dommett, a marketing guru and director of the Cor Agency, and Blackley, a former chief executive of Friends of the Earth Scotland, have been forced out.

Many senior members of the SNP are sceptical about Yes Scotland's ability. Since its launch in May 2012, the cross-party campaign, which includes the Scottish Greens and Scottish Socialists as well as the SNP, has failed to move the opinion polls, which remain frozen at two-to-one against independence.

One SNP source claimed the party was "carrying" Yes Scotland, saying: "We keep getting told things are wonderful, but they're not delivering on the ground for folk, that's quite clear."

Blair McDougall, Better Together's campaign director, said: "It looks like Yes Scotland's refusal to release details of donations is an attempt to cover up a campaign in crisis.

"They must come clean and disclose their donors," he said. "A campaign with a genuine breadth of support simply would not be in financial meltdown."

Jenkins said Yes Scotland was evolving, rather than in trouble, and thanked Dommett and Blackley for their efforts. In a statement released last night, he said: "This is a unique campaign that will decide the future of our country, and we are totally focused on winning a Yes vote.

"That means we will continually test and optimise our effectiveness as the campaign evolves and moves through different phases towards September 18.

"Our team is therefore being augmented by a number of creative specialists, with extensive campaign experience, who will help us deliver those messages widely, and in innovative ways.

"I'm confident we now have the range of talents needed for the intensive and exciting period ahead, and that as we move towards the referendum, our marketing approach will continue to lead, to listen to, and to align with, campaign dynamics."