Boris Johnson has said a Brexit agreement can be done in July if both sides are willing to work harder at sealing it.

The British prime minister and European Union leaders agreed on Monday that talks on the future UK-EU relationship should be stepped up to clinch a deal before time runs out at the end of the year.

Talks have so far stumbled over issues including fair competition guarantees and fishing rights, but now there has been an agreement to "intensify" the talks after a video-conference with European Commission President Ursula von der Leyen and the heads of the European Council and European Parliament.

"I don't think we're actually that far apart, but what we need now is to see a bit of oomph in the negotiations," said Johnson, who claimed he told EU leaders that there was a need to "put a tiger in the tank" of the talks.

He continued: "The faster we can do this the better and we see no reason why you shouldn't get this done in July. I certainly don't want to see it going on until the autumn, winter, as I think perhaps in Brussels  would like. I don't see any point in that, so let's get it done."

Britain left the EU on 31 January and its relationship with the bloc is now governed by a transition arrangement that keeps previous rules in place while the two sides negotiate new terms. 

There had been little optimism ahead of Monday's meeting that there would be much progress.

"The parties agreed... that new momentum was required," they said in a joint statement after Johnson joined the leaders of the EU's three main institutions for a video-conference.

"They supported the plans agreed by chief negotiators to intensify the talks in July and to create the most conducive conditions for concluding and ratifying a deal before the end of 2020."

Negotiators have made very little progress towards a trade pact and the talks have all but stalled over issues such as fair-competition guarantees and fishing rights.

London confirmed last week that it had no intention of extending the transition period beyond the end of this year, and this decision was noted by the leaders at Monday's meeting, according to the statement.

Some fear that, with the two sides so far apart and little time left to negotiate, London's decision not to extend the transition period may lead to a departure without agreement on things like trade that could compound the economic damage caused by the coronavirus crisis.

One EU diplomat said that, despite plans to speed up negotiations, major progress was unlikely until after the summer, when London would "scramble to get something done" at the eleventh hour.

Jill Rutter, from the UK in a Changing Europe think-tank told a Brexit panel discussion on Monday that there could be a "very thin and unambitious deal."

"I think it would be totally wrong to think that the UK will be so desperate that it will move heaven and earth to avoid no deal," she said.