By Alfredo Corchado

Texas Gov. Greg Abbott said Wednesday the state is accepting Mexico's offer to provide assistance in the wake of Hurricane Harvey, including vehicles, boats and food.

Mexico, in a diplomatic note Tuesday, provided a long list of items to help Texas get back on its feet following devastating historic flooding.

Carlos Sada, Mexico's undersecretary for North American relations, said this week his country is prepared to offer relief that includes troops, convoys of food and medicine, portable showers and water.

"Texas and Mexico share more than half the border," Sada said. "There are families, marriages, businesses that bind our two sides. This is about being good neighbors."

In Washington, Department of Homeland Security spokesman David Lapan said Tuesday, "If a need for assistance does arise, we will work with our partners, including Mexico, to determine the best way forward."

On Tuesday, President Donald Trump accepted an offer from Singapore to lend four of its CH-47 Chinook helicopters for rescue efforts. Trump spoke by phone with Prime Minister Lee Hsien Loong as he flew to Texas, and accepted the offer, according to Lee's office. Singapore's Air Force has trained since 1995 with the Texas Army National Guard.

To unauthorized immigrants seeking shelter from Harvey's devastation, Sada said: "Don't be afraid to come out. There is no deportation operation underway. We have the assurance of Gov. Abbott and the mayor of Houston."

Mexico's offer of help comes at a crucial and tense time for the U.S.-Mexican relations, which in many ways is largely shaped by Texas.

Beginning Friday, activists are set to launch statewide protests on two fronts. They plan to rally against the state's new ban on so-called sanctuary cities, a law taking effect Friday. They also plan demonstrations to register growing fears that President Donald Trump will soon end the Deferred Action for Childhood Arrivals program, created by the Obama administration to block deportation of undocumented immigrants who were brought to the U.S. as children.

Moreover, negotiations between the U.S., Mexico and Canada to overhaul the North American Free Trade Agreement _ from which Trump has repeatedly threatened to pull the U.S. _ will resume Friday. No other state has more at stake in those talks than Texas, where nearly half a million jobs depend on the deal.

"Mexico's desire to be humane at a time of such great need contrasts the character and the churlishness coming out of Washington, D.C., and NAFTA," said Tony Garza, a prominent Republican and former U.S. ambassador and now legal counsel with White & Case in Mexico City. "In Texas, given the Legislature's focus these past few months on sanctuary cities sends a clear signal to hundreds of thousands of Texans, particularly Latinos along the Gulf Coast and in Harris County, that we're not with you and in an increasingly purple state, that may mean something."

Garza recalled Mexico taking "the high road" in 2005 after Hurricane Katrina. Mexican soldiers rolled across the border in a 45-vehicle convoy and set up camp at the former Kelly Air Force Base near San Antonio. They served victims 170,000 meals, distributed 184,000 tons of supplies and conducted hundreds of medical consultations. Mexico also shipped humanitarian aid to New Orleans, and former President George W. Bush met with Mexican Marines to thank them.

It's unclear how Trump, who arrived in Texas on Tuesday to survey Harvey's catastrophic damage, will react to Mexico's offer to help. The president and Mexico have had an acrimonious relationship dating back to Trump's first day as a presidential candidate, when he referred to Mexicans as rapists, murderers and criminals.

"We know that Trump is intensely disliked by Mexicans, but in the end Mexicans see us as a neighbor, a place where Americans are good, decent people," said James Taylor, a partner at Vianovo, an Austin-based consulting firm, and chairman of the Aquila Alliance, a Texas group dedicated to promoting closer relations between Texas and Mexico. "Mexicans are demonstrating they care about their neighbor _ especially their immediate neighbor, Texas."

On Sunday, as waters rose across southeast Texas, Mexico reached out to Texas. Trump, meanwhile, bullied Mexico on Twitter to pay for his promised border wall. On Monday, he repeated his threat that the U.S. would at some point kill NAFTA.

"We're in a critical and delicate negotiation with NAFTA," said Ricardo Ainslie, director of the Mexico Center at the University of Texas at Austin. "Mexico has been the brunt of a lot of highly pressured, hostile rhetoric. So I think it's very interesting that Mexico is saying in so many words 'Hey, we're present, and we're critical to things that happen in Texas.' They're showing real political maturity."

Texas has its own dicey issues with Mexico. The recently signed SB4 is scheduled to go into effect Friday, barring its possible overturning this week by a federal judge. SB4 effectively outlaws sanctuary cities _ places where local law enforcement limits or refuses cooperation with federal immigration agents _ and gives police the right to ask the immigration status of people they detain. Mexico's vast immigrant population would be affected.

Texas's biggest cities _ Houston, Dallas, San Antonio and Austin _ and other local entities have filed a lawsuit against SB4, and activists remain hopeful that U.S. District Judge Orlando Garcia will rule the law unconstitutional this week in response.

In 2015, Texas and 25 other states blocked the Obama administration, through a federal court ruling, from extending deferred action to an estimated 5 million undocumented parents of children who were citizens or legal residents, as well as to young immigrants who arrived between 2007 and 2010. The ruling was upheld on appeal, and last year, the Supreme Court split 4-4, leaving the lower court's decision in place.

Texas leads a group of 10 states pressuring the Trump administration to end DACA, and in recent days Trump has signaled he may do so. A legal challenge could come as early as Sept. 5. Most affected immigrants live in either Texas or California.

"Yes, we know about Sept. 1 and Sept. 5, but our decision, our willingness to help Texas isn't based on politics," Sada said. "This is a spontaneous reaction to a neighbor in need, and we, based on our own experiences with natural disasters, know recovery periods can take months, years. So we're here with one message: Texas, Mexico is ready to help."

(Staff writers Tom Benning and Todd J. Gillman contributed to this report.)

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