The captain of a Royal Navy nuclear-armed submarine has reportedly stepped back from his role after being investigated over his relationship with Labour MP Joani Reid. Ms Reid’s husband, David Taylor, was one of three men arrested by counter-terrorism police earlier this month on suspicion of spying for China.

The submarine captain — who is married — and Ms Reid were found to have exchanged flirtatious messages, according to reports, citing sources. A person close to Ms Reid, who “voluntarily” suspended herself from the Labour whip “until internal investigations are concluded” following her husband’s arrest, denies this is the case. The Navy probe into allegations that the senior military officer had conducted an inappropriate relationship with Ms Reid was launched last year.

One person familiar with the matter told the Financial Times that, from a “due diligence perspective,” it was necessary to examine any potential blackmail risk.

Additional security checks were reportedly carried out following the arrest of Ms Reid’s husband.

The Ministry of Defence (MoD) is said to have been satisfied with the checks and remains confident that no breach of security occurred.

The captain, who remains in the Navy, reportedly decided to step back for personal reasons this week after the FT contacted the MoD about the matter.

The captain did not face any disciplinary action and has not broken any military rules.

It is claimed that the officer and MP first met as young adults and that there was no physical relationship between the pair, who have not been in contact for more than six months.

Ms Reid has been the MP for East Kilbride and Strathaven since 2024.

A Royal Navy spokesperson told the FT: “The security of the nuclear deterrent is our highest priority, and we have robust processes in place to protect the security of our people and capabilities. We will not comment on individual cases.”

A spokesperson for Ms Reid declined to comment when approached by the newspaper.