Around 1,000 EDL protesters have made their way along Whitehall before taking a position on the pavement across the road from Downing Street.
A much smaller group of anti-fascist demonstrators gathered opposite them holding an "EDL Racists" banner.
Both sides traded insults but were kept apart by officers and barriers.The EDL supporters chanted: "We hate Cameron."
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Union officials are expected to meet next week to plan further stoppages if talks fail to resolve the dispute.
Natalie Sharp and Christine Bicknell appeared in court over an alleged incident at a Lidl superstore in Wallington, south London.