Tidewater and activist investor Bob Robotti have called a truce in their fight for control of the company.

The Houston offshore giant announced on Monday that it had agreed to add Robotti, of New York's Robotti & Co, to its board of directors, while Robotti will drop his efforts to put himself and two others on Tidewater's board.

"I have been a large and long-term investor in Tidewater because I believe in the potential of the company, its assets and its current leadership team," Robotti said in a statement.

"I would like to thank the board for its constructive approach to our discussions, and I am excited about the future for Tidewater and bringing value to its shareholders.”

In March, Robotti — Tidewater's second-largest shareholder — filed papers with the Securities and Exchange Commission pushing for the three board seats after taking a more active role in the company in October 2019, arguing for more aggressive consolidation.

In the March filing, he said he had hoped to work with the company in a "constructive manner" to bring the new members onto the seven-member board.

Tidewater fired back that Robotti had a financial stake in a competitor and had pushed them to merge. The competitor was not named, but regulatory filings show Robotti had 80,000 shares of Seacor Holdings before the company was taken private by American Industrial Partners last month.

The agreement sees the board grow to eight members from seven to make room for Robotti, with Robotti agreeing to vote for Tidewater's slate of candidates at the company's annual meeting on 8 June.

Further, Robotti has agreed to maintain a stake in Tidewater of at least 1.43m shares while agreeing to refrain from soliciting proxies, making announcements proposing "certain extraordinary transactions" for the company and selling shares outside public markets.

The agreement will last until 150 days after the 2022 annual meeting.

"We are pleased to welcome Bob to the Tidewater board of directors,” chief executive Quintin Kneen, said.

"We look forward to the contributions Bob can make to our future success and value creation."

The addition of a board seat comes 18 months after Tidewater shrank its board to seven members from 10, a move supported by Robotti.

Both Tidewater and Robotti have spoken about consolidating the struggling offshore sector, which fell into a second downturn in a decade due to the Covid-19 pandemic.

Kneen had spoken about the company's stronger leadership position, streamlined cost structure, operational efficiency and the strength of its balance sheet as putting Tidewater in place to capitalise on opportunities in the offshore sector.

On the company's fourth quarter earnings conference call, Kneen said the worst of the pandemic was behind the company with the fourth quarter showing improvement versus its typical seasonal weakness.