PHOENIX - The Southwest border would get 1,000 new Border Patrol agents and 160 new Immigration and Customs Enforcement officers if Congress approves a request by President Obama for an extra $500 million for security.

The president said that is on top of his previous decision to put 1,200 National Guard troops along the Southwest's border with Mexico.

Details of the plan, released Wednesday, also include new customs officers - the people at border crossings - and two new unmanned aerial vehicles to help monitor border activities. Currently, three UAVs operate along the entire Southwest border.

In his letter to Congress, the president said he actually wants to spend $600 million to secure the Southwest border and enhance federal border protection, law enforcement and counternarcotics activities.

Another $100 million, the president said, would come out of the budget for the "virtual fence" project, which has been halted while the Department of Homeland Security determines if it actually could ever work.

The White House also said a separate $100 million of lower-priority projects for Homeland Security will be "repositioned" in the budget to replace and repair fences along the Southwest border.

The $135 million for the 1,200 National Guard troops being sent to the border will come out of "existing resources" in both the Department of Defense and the Department of Homeland Security.

The details about the president's budget request came just days before White House officials are scheduled to brief Arizona Gov. Jan Brewer on the president's plans to improve border security. They are scheduled to meet with the governor on Monday.

Nothing in Obama's letter to Congress provides specifics on where Obama intends to put those Guard troops, a detail that Brewer also hopes to get on Monday.

The governor said the president told her during their June 3 face-to-face meeting a "majority" would be placed in Arizona, although there has been no confirmation from the White House.

Obama, in his letter to Congress, is urging quick action on his funding proposal.

"This request responds to urgent and essential needs," the president wrote. "Therefore I request these proposals be considered as emergency requirements."

How quickly Congress will act remains unclear.

Republicans, including Sen. John McCain of Arizona, have criticized Obama's plans, calling them too small a response to the situation.

McCain said he wanted 6,000 National Guard troops, with half of them in Arizona. He also said Arizona alone needs 3,000 new Border Patrol agents.

In a statement, McCain press aide Brooke Buchanan said Wednesday that the announcement shows "it appears that the Obama administration has finally realized that the border is not 'secure' as some administration officials have stated." She called the programs a good start but said they are "only a fraction of what is needed to secure the border."

Homeland Security says there already are 20,000 Border Patrol agents, double the number of 2004. About 85 percent of these agents are on the Southwestern border.

Not all the money Obama wants would be going directly to Homeland Security.

The plan calls for $201 million for the U.S. Department of Justice to hire new agents for the Drug Enforcement Administration and provide them with equipment support. Those funds also would finance the hiring of new attorneys and immigration judges, as well as new jails to house "criminal aliens."

And some of the money would help Mexico, at least indirectly, with the U.S. providing support by analyzing DNA and ballistics, and providing technical assistance.

The federal response to the border comes in the wake of passage of an Arizona law that is designed to help crack down on illegal immigration, set to take effect on July 29. It mandates that if police officers stop anyone for any reason, they also must check his immigration status if there is "reasonable suspicion" the person is not in this country legally. Illegal immigrants also could be charged with violating state trespass laws.

Five separate federal court lawsuits already have been filed challenging various provisions of the law, and Obama has directed U.S. Attorney General Eric Holder to review the law to determine its constitutionality.