The government has been unable to confirm whether the outcomes of the Ministry of Defence’s (MoD) latest review will be delivered by next week's deadline.
The headline conclusions from the Modernising Defence Programme (MDP) had been expected by the NATO Leader’s summit in Brussels on Wednesday.
On Friday, after five months of work by the department, Downing Street was unable to confirm whether that would still happen.
The review, also called MDP, is looking to make efficiency savings and ensure the Armed Forces are fit for the 21st Century.
It was deemed necessary to assess the workings of the MoD following the emergence of new intensifying cyber and hybrid threats, and a potential £20bn hole in the equipment budget.
Professor John Louth, Director of Defence Industries and Society at the Royal United Services Institute, told Forces News that the MoD was effectively "wrestling with jelly":
"By definition, there will have to be some changes to that programme.
"If we want something like a ballistic missile defence programme to be part of the UK Defence portfolio going forward, that’s a huge investment that will have to come at the expense of something else."
The MDP is assessing four key strands: 'Organisation', 'Efficiency Management', 'Business and Commercial Practices' and finally 'Capability and Force Structure'.
Unpicking the fifth biggest department in government is a complicated task.
Former Chief of the General Staff Lord Dannatt says he believes the Prime Minister needs to increase spending:
"To maintain our place in the world, to be a dependable ally for the Americans we need to spend more on defence. We’ve never spent so little."
Former Defence Minister, Liberal Democrat Sir Nick Harvey says there will be competing demands from the three forces:
"Everybody realises that their bit of the defence world is potentially under threat, so there’s a lot of jockeying for position.
"You have to start recognising that people can be talking with forked tongues and you work out what really does make sense and seem to add up to a coherent vision and what you have to then let go by the wayside."