CK Hutchison’s 3 UK is reportedly suing rival EE for £167 million it claims to have lost on a network sharing agreement between the two companies.

According to a report by financial publication This is Money, the issue relates back to 2010, when Orange and T-Mobile merged in the UK to form EE.

At the time, 3 UK gave its blessings to the tie-up on the grounds that it would be able to access 3,000 of EE’s 3G phone masts, as it had a similar agreement with T-Mobile through Mobile Broadband Network Limited (MBNL) – a dedicated network sharing company formed in a joint venture partnership between the companies.

Six years on, court papers reportedly filed by Hutchison claim EE provided access to just 1,301 sites, which hampered the former’s network roll out, and resulted in estimated losses of £127.9 million because it was not able to access the remaining sites, as well as an expected £39 million in further losses.

An EE spokesperson reportedly hit back, telling the publication: “We strongly reject the allegations and will contest them vigorously.”

In February 2014, the same two companies struck a similar networking sharing agreement, but for 4G, to share some of the costs of the network roll-out.

Hutchison’s takeover bid to acquire O2 in the UK, which would have seen it overtake EE as the country’s market leader, was blocked by European regulators earlier this month.