The move marks a rare public rebuke by international proxy firms against the leader of a top-tier Japanese firm, and comes just as the scandal-hit automaker struggles to move on from the legacy of Carlos Ghosn, its ousted chairman who stands accused of financial misconduct.

It also underscores the precarious position of Saikawa, who was groomed for leadership by Ghosn but appears unable to mend a relationship with Renault that one source said appeared to be in jeopardy.

Institutional Shareholder Services recommended shareholders vote against Saikawa as director at Nissan's annual general meeting this month, to ensure a "clean break" from the Carlos Ghosn era. Ghosn, first arrested in November, is awaiting trial on financial misconduct charges. He denies all the charges against him.

"When the company needs to break from the past and build a strong board with fresh members, the reelection of Hiroto Saikawa, who has been on the board for 14 years and worked closely with Carlos Ghosn, does not appear appropriate," Institutional Shareholder Services said in a research note.

The firm also advised shareholders to vote against the nomination of Moto Nagai to Nissan's board, saying the former executive of Mizuho Financial Group served as an independent auditor at Nissan during Ghosn's tenure, and "shares responsibility" for failing to exercise oversight of Ghosn's alleged wrongdoing.

Another proxy adviser, Glass Lewis, similarly told shareholders not to vote for Saikawa, who needs the support of at least half of voting shareholders at the June 25 meeting to be reappointed.

"We cannot confidently support the nomination of Mr. Saikawa who - as the representative director and president of the Company - should have taken greater steps in performing its oversight responsibilities in the misconduct of the board members," it said in a report to clients.

Nissan declined to comment on the recommendations, which were both published on Friday.

ALLIANCE CRISIS

A recent push by Renault to block a governance overhaul at Nissan has put the Franco-Japanese automaking alliance in jeopardy, a person familiar with Nissan's thinking told Reuters.

The two-decade-old partnership was plunged into fresh crisis this week after Renault signaled it would block its partner from adopting planned governance reforms unless the French automaker received more say in the new system. Nissan has publicly called that demand "most regrettable".

"I have to say that they are endangering the alliance. They have to be very careful not to antagonize Japanese people, shareholders," the person said, referring to Renault.

"Renault has been saying the alliance is important and irreversible but what they are trying to do is to break the alliance," the person said, declining to be identified because of the sensitivity of the issue.

By abstaining from the governance vote, Renault would effectively block the new governance system - which includes three committees - as adoption requires two-thirds approval.

The rift lays bare the deep strain between the two automakers, whose alliance has been under pressure since Ghosn's arrest. What's at stake now may be even bigger than their vast alliance, which includes Mitsubishi Motors.

Renault and Fiat Chrysler Automobiles (FCA) are looking for ways to resuscitate a collapsed merger plan and secure Nissan's approval for that deal, Reuters reported this week. Nissan is, therefore, poised to urge Renault to significantly cut its 43.4% stake in Nissan, Reuters has reported.

Nissan recently said it would abstain from voting on the FCA-Renault merger, although both FCA and Renault later blamed the failure of that deal squarely on the French government.

(Reporting by Linda Sieg and Naomi Tajitsu in Tokyo and Shriya Ramakrishnan in Bengaluru; Writing by David Dolan; Editing by Richard Pullin and Christopher Cushing)

By Linda Sieg and Naomi Tajitsu