WASHINGTON: President Barack Obama plans to provide Libya's rebels with up to $25 million in urgent, non-lethal aid, a senior US diplomat told lawmakers in a letter obtained by AFP on Wednesday.

The message from Acting Assistant Secretary of State for Legislative Affairs Joseph Macmanus to the US Senate Foreign Relations Committee, sent Friday, shows Washington stepping up its help to embattled opposition forces in Libya.

“I wish to inform you that the president intends to exercise his authority to draw down up to $25 million in commodities and services from the inventory and resources of any agency of the United States government,” he wrote.

“The president's proposed actions would provide urgently needed non-lethal assistance to support efforts to protect civilians and civilian-populated areas under threat of attack in Libya,” said Macmanus.

A memorandum attached to the letter said the aid could include vehicles, fuel trucks, ambulances, medical equipment, protective vests, binoculars, and radios.

The letter, first reported in The Washington Times, came as France said it has sent military advisers into insurgent-held eastern Libya, with Britain and Italy set to follow suit, and Tripoli warned foreign boots on the ground would prolong the conflict.

The developments came as the besieged rebel-held city of Misrata desperately pleaded for help against Libyan leader Moamer Kadhafi's forces, who have been pounding it for more than six weeks.

The bombardment continued on Wednesday, with loud explosions heard mid-afternoon in Misrata, where there was heavy overnight fighting and from which thousands of people are trying to flee.