LONDON (Reuters) - Activist Edward Bramson on Monday made a renewed plea for Barclays’ investors to give him a seat on the bank’s board, as the war of words between his Sherborne Investors fund and the lender’s management ratchets up.

FILE PHOTO: A Barclays sign is outside a branch of the bank in London, Britain, February 23, 2017. REUTERS/Stefan Wermuth

Both camps have begun a back-and-forth courting of shareholders ahead of the bank’s May 2 annual general meeting as Bramson attempts to muscle in on decision-making at the company and push through his proposal for a strategic overhaul of Barclays investment bank.

After both issued statements last week laying out their case, New York-based Bramson again wrote to investors on Monday to say nothing Barclays had said had made him change his view about what needed to change at the bank.

“In our firm’s professional opinion, the stubbornly low valuation that the market accords to the shares of Barclays will continue until the board finally adopts a strategy that is more realistic and shareholder orientated,” Bramson said.

Barclays said last week that it plans to stick to its efforts to improve performance at the investment bank rather than scale it back in size.

Given that, Bramson reiterated his call to join the board.

“Our public investment record shows that we have consistently assisted boards, that were initially reluctant, to deliver major increases in value for all of the shareholders,” Bramson said.

“We believe that, given mutual goodwill, and some change in perspective, Barclays offers similar opportunities.”

However, Barclays’ defense against the activist received a boost over the weekend after shareholder advisory group Glass Lewis recommended investors vote against Bramson’s bid to join the board.

While Glass Lewis said the activist’s arguments had some merit, with shareholders getting “fairly mediocre returns”, it none the less took a dim view of the motion.

“We ultimately believe support for Sherborne’s proposal would entail considerably greater risk and uncertainty and, based on available disclosure, would be predicated on substantially unknown strategic intentions,” the advisory group said.