The Trump administration is planning to offset the steep cost of a Mexico border wall by instructing the Department of Homeland Security to cut spending on surveillance technology and freeze the pay of federal officers in the 2019 fiscal year, according to a report released Wednesday by the Democratic staff of the Senate Homeland Security and Governmental Affairs Committee.

The report, which the staffers said was based on information provided to them by "a whistleblower" in late November, said the White House Office of Management and Budget (OMB) told DHS to boost its projected spending on border wall construction for the 2019 fiscal year to $1.6 billion, an amount that would be "$700 million more than the Department's original budget request."

The $1.6 billion would be used to build additional physical barriers in the Rio Grande Valley of South Texas, the border's busiest sector for illegal immigration. To offset some of the costs, OMB instructed DHS to decrease its funding request for border security technology and equipment by nearly $175 million, the report said.

"OMB acknowledged that reductions to RVSS technology are necessary 'to offset the costs of Presidential priorities,' " the report said.

The cuts include a 50 percent spending reduction on Remote Video Surveillance Systems (RVSS), the network of video cameras Border Patrol agents rely on heavily to monitor illegal border traffic. The mobile cameras have infrared technology that allows them to track smugglers and illegal border-crossers at night.

"When [Sen. Claire McCaskill (D-Mo.] visited the border earlier this year, she was told by many of the folks she spoke with along the front lines that technology needs were their highest priority, not a border wall," said Drew Pusateri, a spokesman for the Senate committee's Democratic minority. "So it's a concern to see technology funding reprogrammed for wall funding that wasn't even requested by the department itself," he said.

DHS was also told to strike tens of millions in requests for the boats, helicopters, dirigibles, planes and other equipment that U.S. Customs and Border Protection (CBP) uses to detect and track low-flying aircraft, smugglers' vessels and illegal traffic along the border.

Tyler Houlton, a DHS spokesman, declined to comment on the report. "It is clear that the President is committed to securing the borders and supporting the men and women of DHS," he said.

But according to the Senate report, the White House rejected DHS's request to increase pay for civilian law enforcement officers, including CBP inspectors at ports of entry along the U.S.-Mexico border that "are short thousands of officers."

President Trump has ordered DHS to put 5,000 additional agents along the border, despite latest immigration statistics showing that arrests of illegal migrants are at their lowest point since 1971. Trump has also called for 10,000 more immigration enforcement officers to boost DHS's ability to arrest and deport foreigners living illegally in the United States.

[Arrests along the Mexico border drop sharply under Trump]

DHS officials have insisted they will not lower standards to meet the president's hiring targets. But freezing DHS officer pay could undermine that effort, and according to the report, "OMB instructed DHS to hire 1,000 more new Immigration and Customs Enforcement (ICE) Agents than DHS actually requested, raising the total of new law enforcement personnel ICE must hire in FY 2019 from 1,000 to 2,000."

The spending disagreements outlined in the report were marked "not for public release" and do not necessarily indicate what the final funding levels will be. But the Senate report said they reflect early indications of Trump's priorities for border security funding.

"Additionally, it provides information on the needs of DHS as developed by the agency itself, independent of White House involvement," the report said.