The Greek government will widen its powers over lenders on state support to include veto rights over mergers and acquisitions, according to a draft law tabled on Thursday.

The move comes in exchange for a new batch of government guarantees worth 30 billion euros to help Greek lenders secure funding.

Greek banks have been largely shut out of financial markets in the wake of the country's debt crisis. They have become reliant on state support and European Central Bank funding to refinance their operations.

The government has appointed representatives to sit on the banks' boards since 2008, when all the country's biggest lenders subscribed to a 28 billion euro support fund.

"(The bill) extends the powers of the government representative to board decisions concerning the lenders' legal or financial status, such as mergers and acquisitions," said the finance ministry in a statement.