MEXICO CITY (Reuters) - Alonso Quintana Kawage, chief executive of Mexico's cash-strapped construction company ICA (>> Empresas ICA SAB de CV), is leaving his post, two sources familiar with the matter said, as the company struggles to renegotiate its multi-billion dollar debt load.

The move is part of a wider restructuring aimed at regaining investor confidence after the company's steep slump into debt and a cash crunch under Quintana, the grandson of ICA's founder and who became CEO in 2012.

Both sources said that veteran company executive Luis Zarate would now be appointed CEO, while one of the sources said that current Co-Chief Executive Alfonso Gonzalez Migoya would remain in his post.

According to one person familiar with the matter, Quintana would still sit on ICA's board and could be given a new position at the company.

A spokesman for the company declined to comment.

The firm, which has defaulted on about $60 million in interest payments since December, saw its net debt reach 51.147 billion pesos (£2.11 billion) in the third quarter as a slump in the peso caused its dollar debt value to balloon.

ICA's shares are down 68 percent over the past year, making it the worst performing stock on the IPC index.

ICA's corporate reshuffle has been unrolled at a dizzying pace, as the firm, which built iconic structures like the towering headquarters of state oil giant Pemex, has sought to convince sceptical investors it is charting a new course.

Orlando Loera, who led the restructuring of Mexican homebuilder Geo (>> Corporacion Geo SAB de CV) over the last three years, was named chief restructuring officer in December. But he was quickly replaced by Guadalupe Phillips, a former Grupo Televisa (>> Grupo Televisa SAB) vice president, in January.

Gonzalez Migoya, non-executive chairman of low-cost airline Volaris, was brought on as co-CEO in December to help carry out the company's operational and financial restructuring while Quintana continued to run operations.

Still, calls for Quintana's ouster began months before the current management shift, one source said.

According to two people familiar with the matter, the latest bout of pressure came from the board, which is presided over by Quintana's father, Bernando Quintana Isaac, and includes other family members. Quintana Isaac served as CEO from 1994 to 2006.

Aided by Rothschild and FTI Consulting, ICA, which has also been hit by a slump in government infrastructure spending, vowed to draw up a restructuring plan by mid-February.

But even as the company has made offers to banks to restructure debt, according to two sources and a document seen by Reuters, the lack of liquidity has hampered ICA's efforts.

One person familiar with the matter expects a plan to be presented in March. The company is slated to report fourth quarter earnings next week.

(Reporting by Alexandra Alper and Roberto Aguilar; Editing by Simon Gardner, Bernard Orr and Miral Fahmy)

By Alexandra Alper and Roberto Aguilar