The start date for the construction of new warships on the Clyde has been delayed, provoking anger from the SNP.

The MoD's chief executive for equipment Tony Douglas told the House of Commons defence committee that he could not provide "a time or date" for when construction of the eight Type-26 frigates would begin.

Newly appointed junior defence minister Harriet Baldwin added: "It could be next year. We do not know yet."

The SNP described the admission as an "indefinite delay" on the frigates, adding that this was "an absolute disgrace" and proved that a "Tory obsession with Trident" was sucking money out of the conventional defence budget.

However, the UK Government denied the Type-26 programme was indefinitely delayed and said it simply had not yet concluded commercial negotiations.

During the 2014 independence referendum, the Better Together campaign said that independence would put Scottish shipbuilding at risk.

One leaflet claimed that Govan and Scotsoun shipyards "will get the order for 13 Type-26 frigates from the Royal Navy" if Scotland voted to stay in the UK.

In November last year, the UK Government announced the Royal Navy was cutting its order from 13 ships to eight.

Speaking to the Defence Committee on Wednesday, Douglas denied a shortage of funds was behind the delays, arguing that they were down to design work on the Royal Navy's order being only 60% complete.

It comes after former first sea lord admiral Lord West told the same committee in June that work on the new ships had been put on hold for 2016 because "there's almost no money available this year, and we are really strapped next year".

Committee chairman Julian Lewis said delays in getting the new frigates into service could end up costing money, as the operating life of the Type-23 ships they will replace could have to be extended.

Lewis said: "It's hardly best value for money to penny-pinch now and then end up spending something like 50-60% more on the project later, as happened with the aircraft carriers."

He said industry insiders and experts had told the committee there was a shortfall of around £750m in the sums needed to press ahead with construction.

Lewis added: "We believe that if the money was there, this programme could start very soon."

Douglas insisted the delays were not for financial reasons and said the MoD was still in talks with BAE Systems over the final design of the warship's communications systems and computer networks.

He added around £1.8bn had already been committed to long lead-time elements of the project.

Douglas said: "If you were building an extension on the back of your house, you wouldn't get it priced if it was only 60% designed.

"We are in a good place right now but with 60% design fixity, this is about driving it to closure, which is the road we are on."

Also speaking to the committee, First Sea Lord Admiral Sir Philip Jones said: "It is not that we are not ready to build it, it is not that we don't have the money to build it, or that we haven't already committed substantial amounts of money for long-lead items.

"We are just optimising with the industrial partner the right way to go into contract. I am comfortable with that."

The SNP said an indefinite delay to the shipbuilding project would be a "betrayal" to workers on the Clyde.

Brendan O'Hara, the party's defence spokesman, said: "This latest blow to the Type-26 programme is an absolute disgrace.

"When I asked about the scale and range of cuts to the Defence budget because of Brexit and the huge cost of Trident - I got no answer. Today, Harriet Baldwin has given us part of the answer.

"Her comments about the Type-26 programme will have been no comfort to the workers on the Clyde who now look like they are facing an indefinite delay .

"This would be an utter betrayal to those workers - their families and the communities that depend on the work. We have had assurance after assurance from Tories at Westminster and Scotland and now we are facing the continuing uncertainty and mismanagement of this vital project."

O'Hara added: "The enormous cost of Trident appears to be spiralling out of control - and it would be completely unacceptable and unforgivable if the Clyde yards had to pay the price for the Tory obsession with Trident - a weapon of mass destruction that 58 out of Scotland 59 MPs opposed this week - and an economic black hole caused by Brexit."

The UK Government said it remains committed to the Type-26 programme and that it wished to begin production as soon as possible.

A spokesperson said: "The UK Government is committed to building ships on the Clyde and to the Type-26 programme.

"Over the next decade, we will spend around £8 billion on Royal Navy warships and, because Scotland voted to remain part of the UK in 2014, will continue to be an important manufacturing base for them."