BOGOTA (Reuters) - Avianca Holdings SA <AVT_p.CN> is not for sale and talks with other airlines are efforts to look for possible partnerships that will speed up growth, the president of the company's board and its top shareholder said on Thursday, after recent reports the airline was up for grabs.

Sources have told Reuters that United Continental Holdings Inc <UAL.N>, Delta Air Lines Inc <DAL.N> and China's HNA Group are interested in purchasing Avianca and Avianca Brasil, both controlled by Bolivian-born entrepreneur German Efromovich's Synergy Group.

"Avianca is not for sale. Alliance conversations happen constantly every day," Efromovich told Colombia's Caracol Radio.

Deals with other airlines could allow Avianca to renovate its fleet of planes with more efficient aircraft sooner, he said.

The company is also examining a possible reorganization that may reduce executive positions, Efromovich said.

Avianca Holdings, which operates flights in Colombia, Peru, Ecuador, Central America and the Caribbean, delayed receipt of 130 planes in March and has cut $1.4 billion of investments over the next 30 months.

The company transported 28.3 million passengers to 105 destinations in 2015.

(Reporting by Luis Jaime Acosta, writing by Julia Symmes Cobb; Editing by Phil Berlowitz)