By Jon Robinson Tesco Mobile fell into the red despite its sales passing the £1bn mark during its latest financial year, it has been revealed. The provider, which is a joint venture between the supermarket giant and Virgin Media 02, has reported a pre-tax loss of £449,000 for 2023, according to newly-filed accounts with Companies House. The loss comes after the business posted a pre-tax profit of £8.3m in 2022. The results also show that Tesco Mobile’s revenue increased in the year from £969.5m to £1.05bn, helped by a rise in the sale of premium handsets. A statement signed off by the board sa…