West Ham have been taken over by asset management company CB Holding. Chairman Bjorgolfur Gudmundsson and vice-chairman Asgeir Fridgeirsson have resigned from the club's board.
The new non-executive chairman will be Andrew Bernhardt, a senior director with Straumur Bank, which is the major shareholder of CB Holding.
He told the club's website: "I can assure fans we will sanction investment in new players, but all within the parameters of sensible budgeting."
He added: "CB Holding has no intention of changing the executive management or direction of this club.
"It will be my job to help facilitate this continued process on the pitch, while ensuring the club's success is built on a strong financial footing.
"We have an initial two-year plan, which includes improving the infrastructure at the club, and we will be getting to work on this as soon as the new board is appointed."
Hansa, the holding company for West Ham, had until Monday 8 June to prevent creditors seizing its assets and forcing the sale of West Ham and CB Holding was set up by the creditors last week.
Gudmundsson said: "I want to thank everybody at Upton Park for unforgettable years. As my fortunes have changed I now have to withdraw from the board of directors.
"I do that with great regret but I am convinced this change of ownership and control of West Ham will advance the club.
"I will remain forever a West Ham fan and hope I will have many returns to West Ham."