Defence Secretary Ben Wallace insisted that the huge overhaul is needed to ensure that the military is 'deployable and lethal'.
But Labour claimed 'size matters' and the government had reneged on the PM's election vow by cutting regular Army numbers from 82,000 to 73,000 by 2025 – albeit that is 500 higher than originally expected.
The shake-up will see the creation of a new Union Division, with Mr Wallace saying he wanted the army to be at the 'heart' of the UK in an apparent rebuke to Nicola Sturgeon's separatist drive.
Regular forces will be combined with a reserve of 30,000, which will take the lead on civil contingencies.
A brigade of tanks and armoured vehicles is set to be based in Germany, despite the Cold War presence only recently being wound down.
Mr Wallace said the Government has provided the resources for a 'generational modernisation' of defence, with £41.3billion being injected into army equipment and support over the decade – £8.6billion more than had been planned prior to the Integrated Review.
He said: 'The Army will now be reorganised to operate on a continuous basis, fielding all the relevant capabilities for this era of constant competition and persistently engaged around the globe supporting our partners and deterring our adversaries.
Defence Secretary Ben Wallace insisted that the huge overhaul is needed to ensure that the military is 'deployable and lethal'
Labour claimed 'size matters' and the government had reneged on the PM's election vow by cutting regular Army numbers from 82,000 to 73,000 by 2025 – albeit that is 500 higher than originally expected
'Crucially, it will also be an army designed for genuine warfighting credibility as an expeditionary fighting force that will be both deployable and lethal when called upon to fight and win.'
Mr Wallace said the Army will be 'leaner but more productive', also telling MPs: 'Prioritising speed and readiness over mass and mobilisation but still be over 100,000-strong – integrating regulars and reserves as well as all the civil servants and partners from the private sector.'
The Defence Secretary said the army of the future will have six 'distinct' elements, including having more personnel deployed for more time via a 'new network of regional hubs' in places such as Oman and Kenya.
It will be capable of fielding a division throughout the decade as it makes key contributions to Nato warfighting, MPs heard.
Upgraded equipment, a new Experimentation and Trials Group to be established in 2022 to 'stay at the cutting edge' of technology, and being at