London (CNN) -- Police served a notice Thursday on WikiLeaks founder Julian Assange demanding that he appear at a police station in connection with his extradition, after he sought asylum last week at the Ecuadorian Embassy in London.
The surrender notice was served "upon a 40-year-old man that requires him to attend a police station at date and time of our choosing,"a Metropolitan Police statement said.
"This is standard practice in extradition cases and is the first step in the removal process.
"He remains in breach of his bail conditions, failing to surrender would be a further breach of conditions and he is liable to arrest," the statement said.
Police declined to give further details on the date on which he must report or exactly how the notice was served.
The embassy confirmed that a letter was delivered to Assange by police "via the Ecuadorian Embassy."
The embassy separately received a letter from the UK Foreign Office on Thursday reaffirming its commitment to "promoting excellent bilateral relations" between the two countries, it said in a statement.
"The Government of Ecuador will continue to foster good relations with the UK Government whilst assessing Mr Assange's application for asylum," the statement said.
Assange is seeking to avoid extradition to Sweden over allegations of rape and other sex crimes. He has been arrested in absentia, Swedish prosecutors have said.
He was arrested in Britain in 2010 because Swedish authorities wanted to question him about the allegations of rape and sexual molestation -- claims that he denies. His bail conditions included staying every night at the home of a supporter outside of London.
He went to the Ecuadorian Embassy in London on June 19 to seek asylum.
Two days later, the Metropolitan Police said he had violated the conditions of his bail and would be arrested if he left the embassy. Diplomatic protocol prevents police from entering the embassy to arrest him.
Two women have accused Assange of sexually assaulting them during an August 2010 visit to Sweden in connection with a WikiLeaks release of internal U.S. military documents. He was arrested in Britain that December and has been fighting extradition ever since, saying the allegations are retribution for his organization's disclosure of American secrets.
WikiLeaks, which facilitates the anonymous leaking of secret information, has published about 250,000 confidential U.S. diplomatic cables, causing embarrassment to the government and others. It also has published hundreds of thousands of classified U.S. documents relating to the conflicts in Iraq and Afghanistan.
Assange sought refuge at the embassy five days after the Supreme Court of the United Kingdom dismissed a bid to reopen his appeal of the decision to send him to Sweden -- his last option in British courts.
British officials have met with Ecuadorian authorities, but no information has been released about those meetings.
It is unclear when Ecuador will make a decision on Assange's asylum request.
CNN's Alexander Felton, Claudia Rebaza, Laura Smith-Spark and Stephanie Halasz contributed to this report.