MADRID (Reuters) - Spanish bank Sabadell's board will meet on Monday to discuss an all-share offer from bigger rival BBVA that was worth around 12 billion euros ($12.9 billion) when it was announced last week, newspapers including La Vanguardia said.

Sabadell was not immediately available for comment.

La Vanguardia said the meeting would start around noon (1000 GMT), without providing any further details.

The meeting comes after Sabadell lined up advisers Morgan Stanley ( MS ) and Goldman to assess its options.

On Wednesday, BBVA said it had proposed to offer one newly issued BBVA share for every 4.83 Sabadell shares, a premium of 30% over Sabadell's April 29 closing price. Sabadell said it's board would assess the proposal.

Based on Friday's closing prices of 9.850 euros for BBVA and 1.8850 euros for Sabadell, the offer would be worth around 11 billion euros, a premium of about 8%.

At 0745 GMT, BBVA shares were down 0.8% at 9.77 euros. Sabadell's were up 1.4% at 1.9115 euros.

($1 = 0.9289 euros)