Instagram has announced new features it says will help teenagers and parents manage time spent on the app.

Parents will be able to see how much time their children spend on Instagram and set time limits, while teens will get reminders to take a break.

It comes a day before Instagram chief Adam Mosseri is due to appear before US Senators investigating online safety.

Instagram has been under increasing pressure over teens' use of the platform in recent months.

Its internal research suggesting that teens blamed Instagram for increased anxiety was the first in a series of revelations in France Haugen's leaked documents from inside Facebook.

The US Senate Committee is expected to quiz Mr Mosseri on Instagram's internal information on child safety and its plans - as well as what the committee calls "potential legislative solutions".

The timing of the announcement by Instagram was "interesting", said social media consultant Matt Navarra.

"Instagram's boss will want to have something new and meaningful to show US senators when they grill him... the new features will give worried parents more tools to help keep their children safe when using Instagram, but many will wonder why it has taken them so long to act."

In his blog post, Mr Mosseri announced the launch of the "take-a-break" feature, which he had tweeted about in November.

It will be launched on Tuesday in the UK, Ireland, United States, Canada, Australia and New Zealand, he said.

"If someone has been scrolling for a certain amount of time, we'll ask them to take a break from Instagram and suggest that they set reminders to take more breaks in the future," Mr Mosseri wrote.

The feature would also show them tips from experts to "help them reflect and reset", he said.

Teenage users will get notifications to turn on break reminders, he said.

Instagram also said it will launch a new tool for parents in March 2022, which will let them see how much time children are spending on Instagram, and set time limits for the app. Another companion feature will allow teens to opt-in to a system that will notify parents if the teenager files a report against an Instagram user.

Time limits already exist on Instagram - users can voluntarily set a time limit per day and receive a notification when that limit is hit.

Mr Mosseri also unveiled a new system to bulk-manage Instagram accounts.

Starting in January, a new system will let any user see all their posts, or all their likes and comments, in a chronological list - and select several at once to delete in bulk.

"While available to everyone, I think this tool is particularly important for teens to more fully understand what information they've shared on Instagram, what is visible to others, and to have an easier way to manage their digital footprint," Mr Mosseri wrote.

Among the other measures announced on Tuesday were an expansion of the app's limits on messaging teens - so that now, people will no longer be able to tag or mention teens who do not follow them.

And another feature suggests that Instagram will "nudge" users towards other types of content "if people are dwelling on one topic for a while".

Mr Mosseri did not elaborate on what types of content that "nudge" might apply to, how it will work, or when it will be implemented. The only example given, in an image on the blog post, was suggesting a user who had looked at beauty posts might want to explore travel, interior design or dogs.

Ahead of his grilling by US politicians on Wednesday, Mr Mosseri finished his blog post announcing these new measures by saying: "I continue to welcome productive collaboration with lawmakers and policymakers on our shared goal of creating an online world that both benefits and protects many generations to come."

The range of new measures was broadly welcomed by the Molly Rose Foundation, set up in memory of teenager Molly Russell who took her own life in 2017 and who viewed distressing material on Instagram.

"As ever, when such announcements are made, it is the detail of the proposals that will reveal how effective the new measures are likely to be," it warned.

"Shifting responsibility to parents without Instagram also taking additional steps towards greater online safety would not be adequate."

The sentiment was echoed by Sarah Goodall, chief executive of social media consultancy Tribal Impact.

"A lot of children, they're very isolated with their experience on social media," she told the BBC, referring to problems such as cyber-bullying.

In particular, she praised the newly announced facility whereby parents will be able to receive an alert if their child reports another user of the app.

However, Ms Goodall - who is a parent herself - argued that social media companies could, in general, do more to enable parental oversight of their children's activity online.

"A lot of parents that I'm teaching how to be active on social, they don't understand how to work with their children, the conversations to have, the sites to spot - and I do believe that the social platforms could do more to help," she added.