The group were stymied in their attempt to reach Chaeng Wattana Road and take it off protesters camped there under the banner of the People’s Democratic Reform Committee (PDRC).
The red-shirts led by spokesperson Sornrak Malaithong were stopped at Lak Si intersection, where police used a barricade of vans to prevent their advance to a planned confrontation with the PDRC supporters led by Luang Pu Buddha Isara.
Pol Col Chusak Techarakphong, deputy city police region 1, mediated the situation and negotiated with leaders from both sides.
He said the PDRC agreed to open the road on May 18, but the red-shirts want the road reopened on May 12.
The red-shirt supporters then dispersed, saying they would return.
Mr Sornruck said they would return on Sunday, May 11, and take Chaeng Wattana Road back from the PDRC.