Billionaire Patrick Drahi has increased his stake in BT to 24.5% but reiterated that he does not intend to make a full takeover for Britain's biggest telecoms group.
BT is building the country's fibre network, and the British government has in the past warned it would intervene to protect the telecoms group due to its role in building critical infrastructure.
Last year, the government investigated Drahi's involvement after he lifted his stake in BT to 18% before announcing in August that the Franco-Israeli entrepreneur's investment did not pose a national security risk.
BT's shares tumbled as much as 10% last week when it published results last week showing the pressure on its free cash flow from the rollout of the new fibre network.
It also said it would cut up to 55,000 jobs by 2030, when contractors and engineers are expected to have completed the fibre network.
The stock has since recovered those losses but at 147 pence, it is some way below highs of 500 pence seen in 2015.
Drahi's statement today said that he acquired a further 650,000,000 shares but did not intend to make an offer for the group, meaning he cannot do so for six months under UK takeover rules unless circumstances change.
That change of circumstance includes the emergence of a counter offer for BT or if BT's board agrees to a deal.
Drahi's Altice group controls SFR, France's second-biggest telecoms company, and he also has assets in the US, Portugal and Israel.
The stake in the 175-year-old former monopoly positions him to benefit if BT succeeds in its $20 billion bet that its national fibre build will deliver long-term rewards.
Analysts have in the past speculated Drahi could push BT, which has a market capitalisation of about £15 billion, to separate its networks arm Openreach to achieve a higher valuation shorn of the risks related to BT's enterprise and consumer units.
