* BP updates its conflict of interest policy

* Senior staff have three months to disclose relationships

* Staff face potential sacking for failure to comply

LONDON, June 10 (Reuters) - BP employees must disclose any intimate relationships with colleagues or risk losing their jobs, the oil major told staff in a policy update, following the sacking of former CEO Bernard Looney for failing to do so.

The updated conflicts of interest policy, which was communicated to staff via email last week and seen by Reuters, highlights how Looney's sudden departure last September continues to reverberate through the company.

The updated policy "prohibits employees from directly or indirectly managing relatives or those with whom they're in an intimate relationship," according to the memo.

The London-listed company said that employees will face disciplinary action including potential dismissal for failing to comply with the new requirements.

In addition to the updated policy, which is part of BP's code of conduct, thousands of senior leaders are required to declare any intimate relationships with employees or agency workers occurring within the last 3 years. The managers were given a three-month grace period running to Sept. 1 to make such declarations.

BP confirmed the policy update regarding conflicts of interest arising from familial and intimate relationships at work.

"Employees were previously required to disclose and record such relationships if they felt there could be a conflict of interest," the company said in an emailed statement. "Now they are required to disclose intimate relationships at work, whether or not they feel they represent a conflict of interest."

BP concluded its investigation into Looney's conduct with the help of law firm Freshfields earlier this year and has not disclosed its findings or conclusions, two sources familiar with the matter told Reuters.

"The board has looked at the details and is making sure that themes and lessons are taken into consideration and adopted appropriately," BP said in the emailed statement.

BP's board dismissed Looney last December and clawed back up to $40 million of his remuneration. The company said Looney had knowingly misled the board by failing to disclose past relationships.

Looney's departure came after the board investigated similar allegations against him in May 2022, following which Looney gave the board assurances over his past and future conduct.

BP's shares have dropped by over 11% since Looney's departure, underperforming rivals amid ongoing investor concerns over the company's energy transition strategy. Its new CEO Murray Auchincloss, who took office in January, has sought to steady the ship by promising to boost returns.

Auchincloss' partner is also a BP employee, a relationship he disclosed prior to becoming chief financial officer in 2020. ($1 = 0.7859 pounds)

(Reporting by Ron Bousso; Editing by Emelia Sithole-Matarise)