By Lourdes Heredia
BBC News, Washington
President George W Bush's request for $500m to help Mexico in its fight against organised crime may run into opposition from more than one side.
Mexico's government has been cracking down on drugs traffickers
The money he has asked for from the US Congress would form part of a comprehensive two-year plan, to be known as the "Merida Initiative".
White House spokeswoman Dana Perino said the name referred to the birth of the idea at a meeting between Mr Bush and Mexican President Felipe Calderon in the town of Merida last March.
Both governments appear to want to avoid using the name "Plan Mexico", as the programme was dubbed by many observers ahead of Mr Bush's official announcement on Monday.
That name refers to the anti-narcotics package the US established with Colombia in 2000, which has proved controversial.
Andrew Selee, director of the Woodrow Wilson Center's Mexico Institute, told the BBC he believed the two governments wanted to avoid the name so as not to prejudice either Congress or public opinion.
"The idea of comparing this package with Plan Colombia generates resistance in both countries," Mr Selee said.
"At least in the US, more and more voices question the effectiveness of the help that was given to Colombia."
Under Plan Colombia, an assistance programme that has made Bogota the largest recipient of US aid in the western hemisphere, about $600m a year goes to military operations and development projects in drug-growing regions.
Mr Bush's $500m funding request for Mexico is the first step in a programme that will total $1.4bn in two years.
If approved, the money will help pay for intelligence and training efforts, as well as equipment such as helicopters and boats.
Putting the proposal to Congress alongside a request for extra war funding, the Bush administration said that helping Mexico would also help the US.
"Already, President Calderon's decisive actions have had a positive effect in the United States," Ms Perino said in a statement.
"They have disrupted drug trafficker supply lines and have contributed to shortages in cocaine and methamphetamine supply across the nation."
Some 90% of the cocaine entering the US comes through Mexico.
In Mexico, US intervention is viewed with suspicion.
President Felipe Calderon met Mr Bush in Mexico
Before the details have even been released, critics have voiced concerns that the help will come with a price, such as permission to allow US agents to carry weapons and pursue drug traffickers on Mexican soil.
However, US Under-Secretary of State for Latin America Thomas Shannon stressed at a press conference that there would not be "an increase of our presence in Mexico".
He insisted the money would be used to pay for training for Mexico's military and law enforcement agencies and for equipment.
He declined to give more details however, as to spending or any requirements that Mexico's government might have to fulfil, saying the US Congress would have to be briefed first.
Some congressmen contacted by the BBC expressed concern as what they saw as a lack of transparency during negotiations on the initiative.
On Thursday, the subcommittee of Western Hemisphere Affairs of the House of Representatives is to hold a hearing at which the details of the plan should be revealed.
Democratic Congressman Eliot Engel, chairman of the Subcommittee on the Western Hemisphere, said he hoped that the Bush administration would be "more forthcoming" with Congress now that the plan had been announced.
"While I look forward to reviewing the counter-narcotics plan for Mexico and Central America, Congress was not consulted as the plan was developed," he said.
"This is not a good way to kick off such an important effort to fight the increase in narco-trafficking and violence in the region."
Efforts to eradicate illegal drugs plantations have been stepped up
Mr Selee told the BBC it was difficult to predict whether members of Congress would approve the plan because "up until now they have not been a part in the decision-making process".
Factors unrelated to Mexico could also affect Congress's decision, he warned, such as political differences between the Democratic-controlled Congress and the White House.
"Even though the Democrats might want to support help towards Mexico, the plan could turn out into another battlefield between the executive office and the legislative," Mr Selee said.
In other words, the Bush administration may promise a security plan, but if the legislators refuse to give it the green light, the money will not follow.