The Conservative chairman of the Commons Defence Select Committee James Arbuthnot said there were still many unanswered questions over how an independent Scotland would defend itself if voters decided to go it alone.
He said: "At the moment we have no clarity at all as to how the Scottish government intends that an independent Scotland would be defended."
He criticised Holyrood's veterans minister Keith Brown, who he said had failed to provide answers when he came before the select committee.
However, the Scottish MSP insisted that the cost of Scotland defending itself in the event of it breaking away from the UK would not be as high as Mr Arbuthnot suggested.
Mr Arbuthnot said "there would be enormous upheaval and expense" caused by the removal of Trident. He said "quite what would happen, where would it go, how much would that cost, how long would it take" were questions to which there were as yet no answers.
He was unable to put an estimate on the possible cost for Scotland, saying current defence in that country was about "an eighth of the £38 billion" currently spent by the UK - approximately £4 billion/£5 billion.
Mr Brown, however, said the £2.5 billion figure put forward by the SNP was "substantially more than we believe is currently spent in Scotland", which based on current 2007/8 figures was £1.6 billion a year.
Asked why Scotland wanted to be part of Nato, a nuclear alliance, he said: "The idea that Scotland is somehow curious or different or unique in this respect is not true.
"It's a simple case that the Scottish government's position is that we don't want to have these weapons of mass destruction."
Mr Brown said that the SNP's position "puts us right in the mainstream" of other Nato members who do not themselves own any nuclear deterrents, but wish to be part of the defence alliance.
"We believe Nato as a defence alliance is much broader than a nuclear alliance, of course some of the countries involved have nuclear weapons, but we don't want to have that in Scotland - not just because they're very dangerous, Scotland has hosted them for many years now."
Scottish voters will decide on whether to stay or leave the UK in the independence referendum on September 18 next year.
The interviews followed a new report by the committee in which it called for the Government to prepare for the impact of possible Scottish independence on UK defence.
The Commons Defence Committee made the call following an investigation into the Scottish Government's proposals for a defence force, assuming a Yes vote in the referendum next September.
The committee urged governments in London and Edinburgh to set out more information to help voters understand the implications.
The report states: "We recognise that the process of negotiation following a Yes vote would be lengthy and complex.
"For those very reasons, it would be remiss of the UK Government not to make preparations in order to inform its negotiating position.
"We recommend that the UK Government begin now to prepare for the impact of possible Scottish independence.
"It would not be wise to begin contingency planning only after the referendum.
"This does not imply that we believe there should be negotiations with the Scottish Government prior to the referendum, but rather that it would be prudent for the MoD (Ministry of Defence) to scenario-plan."
People across Britain deserve to be presented with as full a picture as possible, the report concludes.
"To date, the information published by both the Scottish Government and UK Government falls far short of requirements," it states.
MPs looked at the Scottish National Party's (SNP) blueprint for an independent army, navy and air force over the course of a year.
The report finds that the proposed £2.5 billion budget cannot be properly judged at this point.
But it calls for more detail on the navy and raises a number of questions about the size and scope of a Scottish army, including costs, troop numbers and base locations.
On plans for an air force, the report states: "We do not currently understand how the Scottish Government expects, within the available budget, to mount a credible air defence - let alone provide the additional transport, rotary wing and other support aircraft an air force would need."
Transition of the Trident nuclear deterrent on the Clyde could not be achieved quickly, it finds.
The Scottish Government has made the removal of nuclear weapons a key part of its independence plan.
"Even with political will on both sides, the replication of the facilities at Faslane and, crucially, Coulport (Argyll), at another site in the UK would take several years and many billions of pounds to deliver," the report states.
"Options for basing the deterrent outside the UK, in the USA or France, even in the short term, may prove politically impossible or equally costly."
MPs also considered jobs and the shipbuilding industry, concluding that the scale of the defence force would "barely provide enough work for a single yard".
Work would have to diversify to secure orders in open competition, the report suggests.
Overall, the defence industry would face a difficult future, according to the report.
Intelligence services in the early years of independence would rely on "goodwill" from the rest of the UK.
Committee chairman James Arbuthnot MP said: "Crucially, we are not making recommendations to the Scottish people. The decision on independence is a matter for them.
"But we do think that Scottish voters need to see answers to the questions that we are asking the Scottish Government to provide in their upcoming White Paper.
"It will be for the Scottish Government to make its case that an independent Scotland can sustain an appropriate level of defence and security."
Mr Brown has said that UK defence policy does not work for Scotland.
"An independent Scotland will have first-class conventional forces playing a full role in defending the country as well as co-operating with international partners and neighbours, something this report fails to acknowledge by ignoring key pieces of evidence," he said.
"Decisions on Scotland's defence and security should be made by those with the strongest interest in them - the people of Scotland - and current UK defence policy is letting Scotland down.
"For example, our geographical position and wealth of offshore and other natural assets make it a priority for Scotland to secure and monitor an extensive maritime environment.
"And yet, under the current arrangements, there is not a single major Royal Navy surface vessel based in Scotland and the RAF has no maritime patrol aircraft since the scrapping of the Nimrod fleet."
He complained that "important" evidence was left out by the committee, including favourable comparisons with the Danish defence budget.
Shadow defence secretary Jim Murphy, Labour MP for East Renfrewshire, said the SNP plan would leave Scotland unable to adequately defend its interests.
"Experts continue to line up to expose the flaws in the SNP's plans," he said.
"Industrial job losses, capability gaps, funding black holes and shrunken forces would all be the defining features of a SNP Scottish defence force."