Major League Baseball says it held "a very good meeting" with Mayor of London Sadiq Khan about playing matches in the capital.
The sport's commissioner Rob Manfred met Khan on Sunday but no deal was agreed about which teams would play, a spokesperson told BBC Sport.
It comes after Khan revealed talks were under way with MLB and the New York Mets to play matches at London Stadium.
Plans to host regular season games in London were abandoned in July.
"Commissioner Manfred and the Mayor of London had a very good meeting on a variety of topics," said an MLB spokesperson.
"Nothing specific has been determined regarding when a game might occur in London and what teams would participate.
MLB has never been played in Europe, but London has hosted games in American football's NFL and basketball's NBA in recent seasons.
Khan said earlier on Wednesday: "We're in discussions about MLB and we want MLB to come to London.
"What we're discussing with Major League Baseball is for them to come here during the summer, which works for us for obvious reasons. They are very excited."
West Ham United are the main tenants at London Stadium, which was built to host the London 2012 Olympics.
Khan, who took over from Boris Johnson in May, threw the first pitch at a New York Mets match last week.
Three NFL matches will be played in London this season, including at Twickenham for the first time.
Khan said: "This shows London is open and is the sporting capital of the world. The rest of the country can benefit from the sporting events and the rest of Europe as well."