Ighalo joined United on loan until the end of the season on deadline day last month from Chinese club Shanghai Shenua.
“Due to the current situation in China, it has been decided that new signing Odion Ighalo will not travel to Spain as it is not guaranteed that he’d clear UK immigration on return should border restrictions tighten on travellers who’ve been in China within the past 14 days,” United said in a statement.
“Odion will stay in Manchester on a personal training and fitness programme so that he will be ready to join in team training sessions when the squad return from the trip.
“This is simply a precautionary measure as the situation continues to be monitored.”
Ighalo, who has played his club football in China for the past three years after joining Changchun Yatai from Watford, was signed as emergency cover for the injured Marcus Rashford.
“Of course he might have liked to have come with the players and got to know them, but the risk (of border restrictions tightening), we don’t want to take that,” said United boss Ole Gunnar Solskjaer.
Rashford and Paul Pogba are also noticeable absentees from the United squad headed to Spain as they will continue their recovery in Manchester.
United are not in action again until they travel to Chelsea in a crucial battle for a top-four finish in the Premier League on February 17.
