A clutch of new General Election polls have shown the Conservative lead over Labour shrinking as the June 8 vote approaches, including one which put Theresa May’s party just six points clear.

The ORB poll for the Sunday Telegraph had Tories down two points in the past week on 44%, six points ahead of Jeremy Corbyn’s Labour on 38% (up four points), with Lib Dems on 7% (unchanged) and Ukip on 5% (down two).

The 38% score equals Labour’s best rating since Mr Corbyn became leader and would see him comfortably outpoll Ed Miliband and Gordon Brown’s election results if repeated on June 8.

In the Sunday Times, a YouGov poll put Tories seven points ahead on 43% (unchanged since a similar poll on Friday), with Labour down two points on 36%, Lib Dems down a point on 9% and Ukip unchanged on 4%.

An Opinium poll for The Observer found the Tory advantage had fallen from 13 to 10 points over the past week, with Theresa May’s party on 45% (down one point), with Labour on 35% (up two), Liberal Democrats on 7% (down one) and Ukip on 5% (unchanged).

And a ComRes survey for the Sunday Mirror and Independent showed the gap between the parties narrowing from 18 to 12 points over the past fortnight, with Tories on 46% (down two), Labour on 34% (up four), Lib Dems on 8% (down two) and Ukip 5% (unchanged)

Although the results are less dramatic than Friday’s YouGov survey, which found the Conservative advantage squeezed to just five points, they tally with the trend in a number of polls which have shown Labour gaining on the Tories after having begun the election race as much as 25 points adrift.

All the surveys were conducted after Monday’s suicide bomb in Manchester.

The ComRes poll found Mrs May was rated best leader to keep Britain safe from terrorism, by a margin of 42% to 16% for Mr Corbyn.

But her ratings on this and almost every other measure had declined over the fortnight since the questions were last asked, while the Labour leader’s had improved.

Labour was preferred by a margin of 42% to 37% for having the “best policies for people like me and my family”. But 51% said that Mrs May would make a better PM, compared with 30% for Mr Corbyn.

The Prime Minister was seen as best choice to represent Britain on the world stage, lead negotiations on Brexit and reduce net migration, while Mr Corbyn was rated best to improve the NHS, look after the interests of hard-working families and protect older people.

The ORB poll suggested a shift towards Mr Corbyn among women over the course of the campaign, with the proportion saying they would vote Labour rising from 31% to 40% since mid-May.

The Opinium poll found Mrs May’s approval ratings had slumped from plus-17 to plus-11 over the week, while Mr Corbyn’s rose from minus-18 to minus-11.

Opinium questioned 2,002 people from May 23 to 24.ComRes interviewed 2,024 adults from May 24 to 26.ORB interviewed 1,500 voters on May 24 and 25.YouGov’s poll of 2,003 people was conducted on May 25 and 26.