(Adds comments from Senator Cardin)
WASHINGTON/LIMA, April 10 (Reuters) - U.S. President Donald Trump canceled his first official trip to Latin America, the White House said on Tuesday, triggering a mix of relief and criticism from a region he has repeatedly disparaged over immigration, narcotics and trade.
Trump is weighing how to respond to a suspected chemical weapons attack in Syria, and will send Vice President Mike Pence to the Summit of the Americas in Lima, Peru, in his place, the White House said. The announcement came as Trump railed against a Federal Bureau of Investigation raid on the offices and home of his personal lawyer.
Trump's meetings with heads of state from the hemisphere had been expected to be tense because of his divisive rhetoric and fraught relationships with leaders such as Mexican President Enrique Pena Nieto.
"We're going to miss him," said Mexico's Economy Minister Ildefonso Guajardo, who is expected to talk about efforts to update the North American Free Trade Agreement (NAFTA) with his counterparts from the United States and Canada.
The cancellation prompted at least one regional leader, Bolivian President Evo Morales, to reconsider attending.
"I wanted to meet the U.S. president face-to-face to debate economic and social policies," Morales, a critic of Trump, said in televised comments at a public event.
The cancellation marked a new first for the United States: No U.S. president has ever missed a Summit of the Americas.
Richard Feinberg, an architect of the first summit in 1994 when he worked for the Clinton White House, called Trump's change in plans a "shocking abandonment of U.S. leadership in our own hemisphere" and said it "leaves a leadership vacuum that others will rush to fill."
Trump had planned to use the summit to urge Latin American leaders to work with the United States and not China on trade, and to adopt a tough stance on Venezuela, a U.S. official said.
For many in Latin America, Trump's decision to skip the summit deepened the view that Trump does not care about the region.
"Predictable," Juan Jimenez, a former Organization of American States official who is also a former Peruvian prime minister, said on Twitter.
Ana Quintana, an analyst with the conservative Heritage Foundation in Washington, said Trump made the right decision to focus on the more pressing issue of Syria.
Pence "will expand the regional coalition against Venezuelas dictatorship and demonstrate why the U.S. should remain Latin Americas economic partner of choice," Quintana said.
Some felt it might be easier for regional leaders to focus on tough issues like corruption and Venezuela without Trump looming over the talks.
"You have the awkwardness out of the picture," said a Peruvian diplomat who asked not to be named, citing Trump's unpopularity across Latin America.
Democratic Senator Ben Cardin called the Republican president's decision "disappointing" but said it is hard for the United States to show leadership on addressing corruption in other countries because of the way Trump has handled his own "personal conflicts."
"With the investigations in the United States and the decision the president has taken on his own conflicts, he does not have the same moral clarity" to credibly address the topic, Cardin said in an interview.
The FBI raid on Monday was the latest in a series of probes involving people close to the president. His personal lawyer, Michael Cohen, has admitted making a $130,000 payment to porn star Stormy Daniels before Trumps 2016 election. Daniels has said she had sex with Trump in 2006 and was paid to keep quiet about it. The White House has denied that Daniels had sex with Trump, and Trump has said he was unaware of the payment.
Trump believes he has the power to fire Special Counsel Robert Mueller, who is investigating whether Trumps campaign colluded with Russia during the election, the White House said on Tuesday.
Trump has called the raid a "disgrace" and the investigations a "witch hunt" and has harangued the Justice Department and news media outlets.
"When there are investigations going on and he uses his position as president of the United States to try to undermine those investigations - thats what you see in autocratic countries," Cardin told Reuters.
The White House did not respond to requests for a response.
VENEZUELA IN FOCUS
This will be the second trip to the region for Pence, who met with leaders in Colombia, Argentina and Panama in August.
Pence wants to work with regional allies to increase pressure on Venezuelan President Nicolas Maduro ahead of the country's election next month, which has been dismissed by the opposition and regional leaders as a sham, his spokesman said.
Argentine President Mauricio Macri also said Venezuela would top the agenda in Peru. "We're not going to accept the result of the May 20 election," Macri told a press conference.
Peru uninvited Maduro from the summit earlier this year as it condemned the election. Maduro's main rivals are barred from running against him as he seeks re-election despite a crushing economic crisis and foreign sanctions.
Peruvian President Martin Vizcarra told a press conference in Lima that he regretted that Trump was not coming, saying his presence would have been "important." (Reporting by Roberta Rampton in Washington and Mitra Taj in Lima; additional Reporting By Marco Aquino in Lima, Luc Cohen in Buenos Aires, Adriana Barrera in Mexico City and Danny Ramos in La Paz; editing by Jonathan Oatis and Tom Brown)