WikiLeaks founder Julian Assange suddenly called off an announcement he was due to make from the balcony of the Ecuadorian Embassy following news of an "imminent meeting" with British authorities.
The lunchtime speech, due to be made to mark the fifth anniversary of his arrival at the London embassy, was deferred on the advice of his legal counsel.
"Mr Assange's legal team remain optimistic that a satisfactory outcome can be found which respects the British legal process and restores Mr Assange's freedom and dignity," a statement on his behalf said.
Melinda Taylor, of Mr Assange's legal team, told the Press Association: "We have been given confirmation that there will be a meeting with the British authorities.
"We hope that will be soon.
"We don't want to prejudice that meeting because we need this impasse to be resolved.
"There is no legal reason to keep Julian here."
The Foreign Office declined to comment on the development, but there was no indication a meeting was imminent.
Scores of his supporters gathered outside the embassy, including human rights campaigner Peter Tatchell, who said Mr Assange had been "punished enough" by being held in prison, on house arrest or staying inside the embassy for the past seven years.
He said: "The British government could solve this impasse by giving an assurance that Julian Assange will not be extradited to the United States, and by allowing a request by the Ecuador government to give him safe passage to Ecuador.
"If he is extradited to the United States he is likely to spend between 30 and 50 years in prison."
Mr Assange won the backing of a United Nations panel and has seen the Swedish authorities drop a seven-year investigation into sex-related allegations against him.
Speaking to the Press Association before Monday's anniversary, he said there were reasons to be hopeful that the impasse over his case could be resolved.