President Obama, saying he’s convinced that House Republicans will not take action to reform immigration laws this year, vowed Monday to use his executive authority to “fix as much of our immigration system as I can on my own, without Congress.”

Obama set an end-of-summer deadline for officials to give him options for changes he can implement on his own and promised he would “adopt those recommendations without further delay.”

Democratic lawmakers and advocates who have pushed for executive action to reduce the number of immigrants being deported say they expect that Obama will extend temporary legal status to a significant number of the people who would have qualified under the reform bill that passed the Senate a year ago.

One of the leading backers of immigration reform, Rep. Luis V. Gutierrez (D-Ill.), who has sharply criticized Obama recently, said Monday’s statement represented “the president I voted for.”

“The antidote for do-nothingism is doing something, and the president is doing for the American people what the Republican-controlled Congress refused to do,” Gutierrez said.

Republican officials said further executive action by Obama would merely make existing border problems worse. GOP leaders point to the crisis in Texas, in which thousands of unaccompanied minors from Central America have arrived at the border in recent weeks, as a reason for Congress to hold off on passing comprehensive immigration legislation.

Speaking in the White House Rose Garden, Obama sought to turn that argument around. The “argument seems to be that because the system's broken, we shouldn't make an effort to fix it,” Obama said. “It makes no sense. It's not on the level. It's just politics, plain and simple.”

He also repeated that minors who have arrived in recent months will be sent back to their countries of origin. Administration officials have tried to convey that message to the public in Central America, seeking to combat rumors that the U.S. will allow children to stay if they arrive without parents.

“The journey is unbelievably dangerous for these kids,” Obama said. “The children who are fortunate enough to survive it will be taken care of while they go through the legal process, but in most cases that process will lead to them being sent back home.”

This spring, Obama asked Homeland Security Secretary Jeh Johnson to delay submitting a series of recommendations for changing U.S. deportation practices, hoping that holding off would give House Republicans time to come up with a legislative package they could support.

But according to the White House version of events, House Speaker John A. Boehner (R-Ohio) told Obama last week that his chamber didn’t plan to act this year.

In a statement, Boehner said that he had “told the president what I have been telling him for months: The American people and their elected officials don't trust him to enforce the law as written. Until that changes, it is going to be difficult to make progress on this issue.”

“The crisis at our southern border reminds us all of the critical importance of fixing our broken immigration system,” Boehner said. “It is sad and disappointing that — faced with this challenge — President Obama won't work with us, but is instead intent on going it alone with executive orders that can't and won't fix these problems.”

Boehner added that Obama’s previous executive orders “have led directly to the humanitarian crisis.”

Republicans point to Obama’s decision in 2012 to stop deportations of some young people who were brought to the U.S. illegally as children. They say that order, known as Deferred Action for Childhood Arrivals, had given families in Central America false hope.

Administration officials deny their policies are to blame. Instead, they say smugglers have taken advantage of a U.S. law, passed in 2008 under President George W. Bush, that guarantees a hearing to unaccompanied children arriving from Central America and other countries that do not directly border the U.S.

That hearing process can often take more than a year, and it has helped give rise to the belief among some in Central America that U.S. authorities will give a permiso — permission to stay in the U.S. — to children who arrive at the border.

Earlier in the day, the White House began pressing Congress to come up with more than $2 billion in new money to manage the flood of unaccompanied children. In a letter to congressional leaders, Obama said officials needed the money for an aggressive strategy to repatriate recent border crossers as well as for a sustained border security “surge” to fight smuggling networks.

In addition to the money, Obama wrote that the Department of Homeland Security needed greater discretion in how it processed minors who arrived at the border. That would require Congress to amend the 2008 law — a prospect that has angered immigrant advocates.

“America stands at a crossroads on immigration reform,” said Ali Noorani, executive director of the National Immigration Forum. The administration's proposal will be “held up to close scrutiny,” he said.