Mexico's Senate will kick off a special session Thursday morning to begin consideration of laws to implement the country's historic energy reform.
Committees cleared the remaining three of four draft bills spelling out the fine print of the changes, local reports including the El Financiero newspaper said. The first passed committee on Thursday.
Debate is expected to kick off Thursday morning but is not expected to continue for more than six days with weekend sessions unclear.
To become law the reforms must clear the senate and then the lower house of deputies. Passage is expected given that the right-centre National Action Party (PAN) and Pena Nieto's centrist Institutional Revolutionary Party (PRI) have control.
The party "will really be ready for the most important debate in Mexico's legislative history," El Financiero quoted PRI senator Armando Rios Piter as saying.
Left-centre lawmakers from the Revolutionary Democratic Party (PRD) withdrew from the committee debate and opposed advancing the measure, adamant that the reforms gave too much power away from government to corporations and foreign interests.
The remaining three measures passed Wednesday including changes to laws governing state producer Pemex, the country's federal electricity commission and a wide range of others.
The first measure included several oil-sector concessions to the right-centre National Action Party (PAN), including removal of a provision for land expropriation, according to a senate statement.
Instead the law seeks to establish a system to compensate landowners and allow them to benefit from production on their properties, with those agreements subject to federal review.
The law, the centrepiece of energy overhaul spearheaded by President Enrique Pena Nieto, also establishes a local content requirement of 25%, more or less as expected.
The latest proposal also recommends a public tender scheme for pipeline development.