WASHINGTON — The Obama administration spent more money on immigration enforcement in the last fiscal year than all other federal law enforcement agencies combined, according to a report on the government’s enforcement efforts from a Washington think tank.

The report on Monday from the Migration Policy Institute, a non-partisan group focused on global immigration issues, said in the 2012 budget year that ended in September the government spent about $18 billion on immigration enforcement programs run by Immigration and Customs Enforcement, the US-Visit program, and Customs and Border Protection, which includes the Border Patrol. Immigration enforcement topped the combined budgets of the FBI; Bureau of Alcohol, Tobacco, Firearms and Explosives; Drug Enforcement Administration and U.S. Secret Service by about $3.6 billion dollars, the report’s authors said.

Since then-President Ronald Reagan signed the Immigration Reform and Control Act in 1986 — which legalized more than 3 million illegal immigrants and overhauled immigration laws — the government has spent more than $187 billion on immigration enforcement. According to the report, “Immigration Enforcement in the United States: The Rise of a Formidable Machinery,” federal immigration-related criminal prosecutions also outnumber cases generated by the Justice Department.

The 182-page report concludes that the Obama administration has made immigration its highest law enforcement priority. Critics are likely to bristle over its findings, especially those who have accused the administration of being soft on immigration violators.

“Today, immigration enforcement can be seen as the federal government’s highest criminal law enforcement priority, judged on the basis of budget allocations, enforcement actions and case volumes,” MPI Senior Fellow Doris Meissner, a co-author of the report, said in a statement released with the report Monday.

The report by MPI’s Meissner, Muzaffar Chishti, Donald Kerwin and Clair Bergeron, comes amid renewed interest in immigration reform from Congress and the White House.

In the immediate aftermath of the November election, congressional Republicans suggested the time was right to begin reform talks anew. President Barack Obama, who won a record share of Hispanic voters, renewed a previous pledge to make immigration reform a priority.

In the lead up to the election, Obama made several administrative changes to the immigration system, including launching a program to allow some young illegal immigrants to avoid deportation and work legally in the country for up to two years. His administration also refocused enforcement efforts to target criminal immigrants and those who posed a security threat. And just last week, the administration announced a rule change to allow some illegal immigrant spouses and children of U.S. citizens to stay in the country while they ask the government to waive 3- or 10-year bans on returning to the United States. Immigrants who win the waiver will still need to leave the country to complete visa paperwork, but will be able to leave without fear of being barred from returning to their families for up to a decade. The rule, first proposed last year, goes into effect in March.

Republican lawmakers have widely criticized the policy changes, routinely describing them as “backdoor amnesty.” Many of those same lawmakers have said the border needs to be secured before reform can be taken up.

According to the MPI report and Border Patrol statistics, in 2011 agents arrested about 327,000 people at the southern border, the fewest in nearly 40 years. The Homeland Security Department also removed a record 396,906 immigrants that year. In 2012, nearly 410,000 people were removed from the United States.