Foreign Office Minister Jeremy Browne has turned down an invitation to attend talks in Argentina when he visits the Falklands next week.
The Foreign Office said it was "grateful" for the invitation but said Mr Browne had "a full schedule of events" on the islands commemorating the 30th anniversary of the Falklands War.
Mr Browne has previously accused Argentina of behaving in a "domineering" way over the islands.
A Foreign Office spokesman said that while Britain wanted to build a "stronger partnership" with Argentina, it was not prepared to enter into discussions over the sovereignty of the islands.
"We have today received an invitation from Argentina's foreign minister, Hector Timmerman, for Mr Browne to visit Buenos Aires next week," the spokesman said.
"However he has a full schedule of events in the Falkland Islands to commemorate the 30th anniversary of the conflict there. This has been arranged for some time.
"Mr Browne is grateful for the invitation. The UK has a long-standing interest in building a stronger partnership with Argentina on a broad range of issues of mutual interest.
"The only issue that we will not discuss is the sovereignty of the Falkland Islands, unless and until the islanders wish us to do so.
"We will issue a formal response in due course."
Earlier this week, Mr Browne accused Argentina of "domineering" behaviour amid continued tensions between the two countries surrounding the anniversary commemorations.
He described the announcement by the government in Buenos Aires that it was launching criminal proceedings against UK oil firms operating off the Falklands as another attempt to hinder the economic development of the islands.
Diplomatic sources have said they are expecting a "difficult" few months as key milestones in the 1982 conflict are passed.