Iberdrola plans 2-part euro bond increase -lead

LONDON Jan 12 (Reuters) - Spanish utility Iberdrola (IBE.MC) plans to increase the size of two of its existing bonds, an official at one of the banks managing the deal said on Monday.

Iberdrola plans to increase its November 2011 euro bond, by at least 150 million euros ($201 million) and has set initial guidance at mid-swaps plus 180 to 200 basis points, the official said.

Guidance on the planned increase on the existing November 2015 bond, expected to be around 250 million euros, has been set at mid-swaps plus 280 to 300 basis points, the official said.

The lead managers on the deal are ING, La Caixa and SG CIB, said IFR Markets, a Thomson Reuters online news and market analysis service.

Iberdrola is rated A- by Standard & Poor's, A by Fitch Ratings and A3 by Moody's Investors Service.

(Reporting by Natalie Harrison)