"It's a really big step," said Twitter's Vice President of Global Online Sales, Richard Alfonsi. "It makes Twitter's ad platform available everywhere people are tweeting."
The company doesn't break out what percentage of its user base is outside the 33 countries where it currently offering its ad platform, but does say that 77 percent of its active users are outside the US.
"We have huge momentum in this part of our business," Alfonsi noted.
The ad expansion comes two years after Twitter launched its platform for small and medium-sized businesses. The question is, is it too late considering the fierce competition for advertising dollars?
"These products are working really well," Alfonsi said. "In general I think we've accelerated the pace of execution."
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The advertising announcement comes a day ahead of Twitter's board meeting. CEO selection will be in focus, although it's unclear if there's any announcement from the company in the works. Also under investors' microscopes: Whether the company's making changes to its product quickly and effectively enough to get more users on board.
Alfonsi said Twitter had benefited from its new interim leadership by co-founder Jack Dorsey, who took on the role in June after the surprise resignation of CEO Dick Costolo.
"It's been great to have Jack in the day-to-day of the company. There's lots of excitement and energy for execution," he said.
Alfonsi said small businesses had always "had a special place in" Dorsey's heart, although the plans to roll out this small business platform were in place before Dorsey became interim CEO.
Now, with Twitter shares trading about a dollar above the company's IPO price, and well below where most individual investors bought in, commentators are likely to ask whether this ad expansion is sufficient to reassure investors awaiting a product turnaround.
See more posts from Julia Boorstin at mediamoney.cnbc.com