Manila - About 20 farmers slipped past tight security around the Philippine presidential palace Tuesday and briefly picketed at one of the gates of the sprawling compound.

The farmers were able to enter the "no-rally zone" around the Malacanang palace in Manila by taking public transportation.

They gathered outside the New Executive Building, just a few metres away from where President Gloria Macapagal Arroyo and her cabinet members were scheduled to hold a meeting.

The farmers unfurled anti-government banners and took off their shirts to demand Arroyo make good on her promise to place her family's 157-hectare sugar plantation under agrarian reform.

Palace security guards rushed to stop the rally 10 minutes later and herded the group to the nearest police station for investigation.

The farmers alleged that Arroyo promised them seven years ago that she would redistribute the plantation owned by her husband's family in the central province of Negros Occidental.

The farmers arrived in Manila last week to seek an audience with Arroyo but had yet to met her.

The head of the Presidential Security Group reprimanded the guards on duty for failing to stop the rally and ordered an investigation into the breach of security. (dpa)