Both outlets will be allowed to maintain their Twitter accounts, the company said.
Critics have said that the focus on advertising by Silicon Valley companies is misguided because far more disinformation was spread through free posts, tweets, videos and other content.
In April, Reuters reported that RT and Sputnik were part of a plan by Russian President Vladimir Putin to swing the USA presidential election to Donald Trump and undermine voters' faith in the American electoral system, according to three current and four former US officials.
RT says the allegation is "absolutely groundless and greatly misleading".
Twitter said last month it had suspended about 200 Russian-linked accounts as it investigates propaganda efforts related to last year's election race.
"We do not take this decision lightly, and apply it in the context of our commitment to guarantee to the users of Twitter the integrity of the service", adds the same source.
Twitter also said it would donate the estimated $1.9 million it received from the two Russian groups since 2011 "to support external research into the use of Twitter in civic engagement and elections, including use of malicious automation and misinformation".
RT, an English-language news channel, accused Twitter's sales staff of pressuring it to spend big on advertising in 2016 ahead of the election.
RT editor-in-chief Margarita Simonyan made similar remarks, saying Twitter's actions could lead to retaliatory measures against United States media.
A spokesperson for top Senate Intelligence Committee Democrat Mark WarnerMark Robert WarnerTrump: Why isn't Senate looking into "Fake News Networks"?
Technology giants Facebook and Google are also on the hot seat with lawmakers. Russian Federation has denied interfering in the election.
On Wednesday, Twitter announced a plan to increase ad transparency on its platform, including political and issue-based ads.
The legislation by Sens.
"State-owned Russian media made increasingly favorable comments about President-elect Trump as the 2016 U.S. general and primary election campaigns progressed while consistently offering negative coverage of Secretary Clinton".
The outlets are each owned by the Russian government.
GM Reaches $120m Settlement With States Over Switches
Of cases that have gone to trial, individual drivers have had little luck holding GM liable for their collisions. The switches played a role in at least 124 deaths and 275 injuries, according to a victims' fund set up by GM.