Telefonica reportedly pushed back plans to float its O2 UK unit until after the country formally leaves the EU, a move scheduled for early in 2019.

The Spain-based operator, which was expected to hold an IPO for the unit following the country’s 4G and 5G spectrum auctions in April, has decided to wait until the UK leaves the bloc due to uncertainty the exit will create, Press Association (PA) reported.

An IPO of O2 UK has been mooted since 2016, but Telefonica is yet to pull the trigger.

O2 faced an uncertain future in the UK since the European Commission blocked CK Hutchison’s proposed acquisition of the company in May 2016, highlighting the effect the tie-up would have on competition.

Telefonica group CEO Jose Maria Alvarez-Pallete said earlier this year that uncertainty in the financial markets, as well as failures of companies making debuts including Aston Martin, reduced confidence among the company’s hierarchy about holding an IPO in 2018.

However, this latest development implies it will not float until at least after March 2019, when the UK is expected to leave the EU.

PA added the latest IPO delay will increase volatility, uncertainty and heighten the perception of a lack of investor appetite in London’s IPO market.

However, analysts believe O2 UK’s IPO is hotly anticipated and could raise up to £10 billion.