One in five people who say they are certain to vote in the independence referendum are still undecided over which side to back, according to a new poll.
Almost half of undecided voters still feel they do not have enough information to make a decision, the TNS survey found.
Among those who said they are certain to vote, 35% support independence, 44% back a No vote, and 20% remain undecided.
Pollsters questioned 996 adults between April 23 and May 2.
Overall, the poll found 42% of people back a No vote, against 30% supporting Yes, with 28% saying they did not know.
In October 2013, TNS asked respondents to say how much information they had to help them make a decision using a scale of one to 10, where one is “I don’t feel I have any information at all” and 10 is “I have all the information I need”.
In October, 31% gave a score of between seven and 10, indicating they felt they had enough information. In the latest poll, this has risen to 49%, but 45% of undecideds still feel they do not have enough information.
TNS also asked voters whether they agreed that the two campaigns so far have been negative rather than positive in their content and tone.
Just over half - 53% - said Better Together had been negative, with 15% disagreeing, while 29% rated the Yes campaign as negative, with 37% disagreeing.
Tom Costley, head of TNS Scotland, said: “It is encouraging that with four months to go until the vote, many more people feel that they have enough information to help them come to a decision. However, many people, particularly the undecideds, are still waiting to be both informed and convinced.
“As the electorate usually claims to dislike negative campaigning, this poll suggests that Better Together may need to consider adopting a more positive tone to its campaigning in the run-up to 18 September.”