3i Infrastructure has agreed to increase its investment in Wireless Infrastructure Group and to acquire the stake owned by Barings LLC's client accounts.
The expected investment by 3i Infrastructure is £186m which will take 3i Infrastructure's ownership of WIG to 91% of the equity with the balance held by management.
Completion is subject to certain third party consents.
WIG is an independent communications infrastructure provider headquartered in the UK.
The business builds and operates communication towers in rural and suburban areas, together with fibre-based networks to enable mobile coverage in large buildings and on city streets.
WIG is fully independent of any network operator and invests in high capacity infrastructure available to all networks.
In April 2016, 3i Infrastructure acquired a minority interest in WIG from Barings, to provide additional capital to support the growth of the business.
Since then, WIG has invested to support customers with the expansion of their networks to deliver greater wireless bandwidth and geographic coverage, and increased resilience.
Its portfolio has grown to almost 2,100 assets across the UK, Netherlands and Ireland.
WIG's small cell business unit delivers high capacity infrastructure into large public venues such as shopping centres, office blocks and stadiums. In September 2017, it launched the UK's first 5G-ready, fibre-connected, outdoor small cell network in Aberdeen, working in partnership with Telefonica.
3i Infrastructure said that among the immediate priorities for it on becoming WIG's majority shareholder would be to support its bid to enable mobile connectivity for the London Underground, which was expected to be procured in 2018.
3i Infrastructure chairman Richard Laing said: 'We are delighted to be taking majority ownership of WIG. After the divestments of Elenia and AWG, this is a good example of the opportunities available to 3i Infrastructure to deploy additional capital in its existing portfolio.'