JUCHITAN, Mexico (Reuters) - Mexico’s president on Monday threw himself into areas badly hit by last week’s devastating earthquake amid frustration at delays in getting food and water to stricken communities where at least 96 people died and 2.5 million were left in need of aid.

Accompanied by several cabinet ministers, President Enrique Pena Nieto took on a busy schedule as he toured the battered southern state of Chiapas, seeking to inspire confidence in the government’s relief effort.

Pena Nieto’s approval ratings have plumbed depths lower than any recent president, and his Institutional Revolutionary Party (PRI) faces a major struggle to retain power in presidential elections next July. The law bars him from seeking re-election.

Speaking in the hard-hit city of Tonala, Pena Nieto urged construction companies to aid rebuilding efforts.

“If construction firms commit to showing solidarity by building a few homes ... construction efforts can be carried out quicker,” he said. “Don’t let anyone take advantage of you, or take control of your affairs. The government is here.”

Mexican cement producer Cemex said on Monday it would donate $1 million worth of aid to reconstruction efforts. The final cost of the quake is likely to be far higher.

Among those with Pena Nieto were Interior Minister Miguel Angel Osorio Chong and Finance Minister Jose Antonio Meade, both potential PRI candidates for the presidency.

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The quake killed at least sixteen people in Chiapas and four others in Tabasco. The vast majority of deaths so far reported were the 76 in neighboring Oaxaca state.

Many Oaxaca fatalities were in the town of Juchitan, where more than 5,000 homes were destroyed. Tens of thousands of others were damaged in the region.

Government officials delivered bags of simple rations including water and canned food on Sunday, but many Juchitan residents complained about the slow pace of assistance.

“We don’t have food or water, we’re desperate,” said Jesus Ramirez, 27, who works in a plastics factory. “We’re trying to eat whatever we can find, any kind of food.”

Much of Juchitan and its surroundings had no running water, and piles of rubble were still restricting access to streets. Electricity was returning, but residents complained officials were slow to conduct house-by-house damage assessments.

Alfredo Jimenez, a 19-year-old engineering student, said he and neighbors banded together to help victims of seven flattened homes in the area, feeling unable to count on the government.

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“We see government people passing by, the army and the marines, but they haven’t offered us anything,” he said.

Margarita Lopez, 56, a domestic worker, lined up for assistance in one Juchitan neighborhood where nearly every house was severely damaged. “Almost nothing has arrived from the government, and we don’t know what else we can do,” Lopez said.

Thursday’s 8.1 magnitude quake was the most powerful to hit Mexico in 85 years, surpassing a 1985 temblor that killed thousands in Mexico City and triggered public outcry over the government response.

That disaster hurt the PRI’s reputation and some analysts believe it contributed to its removal from power in a 2000 vote, ending 71 consecutive years of one-party rule.

Under pressure to do more at home, the government on Monday withdrew an offer to help victims of Hurricane Harvey in Texas. Mexico has been coping with heavy rains and the impact from Hurricane Katia on the Gulf state of Veracruz.

The quake struck off the coast of Chiapas, and Mexico’s national seismological institute said more than 1,000 aftershocks have since been reported.

State-run oil company Pemex said on Monday it has not restarted its Salina Cruz refinery due to the aftershocks.