The veteran-left winger is gathering his top team at a union headquarters in the capital to discuss how to revive the party's dire performance, despite facing criticism that he is obsessed with a metropolitan agenda.
He suggested it could take another two years for signs of improvement to emerge - doubling his previous estimate for seeing an improvement.
He also took aim at Mr Lansman's focus on party control rather than helping Labour win the next General Election.
Watson warned Momentum's founder, Jon Lansman, was plotting to take control of Labour by striking a secret deal with the Unite union boss Len McCluskey.
Scottish Labour leader Kezia Dugdale has backed Jeremy Corbyn despite reports that a group of his supporters are planning a power seizure.
Jeremy Corbyn and Tom Watson have agreed to "strengthen" Labour Party unity after "robust and constructive" shadow cabinet talks at Unison's headquarters in London on Monday (20 March). Dragging the party into this is disappointing'.
Christine Shawcroft, a member of Labour's national executive committee and an ally of Lansman, said the recorded comments were "a non-story", and were primarily "a concerted attempt to interfere in the internal election in Unite for general secretary".
The tape of Mr Lansman's remarks, said to have been secretly recorded at a meeting of a Momentum branch in Richmond, south west London on 1 March, was obtained by The Observer.
"We've seen over the last few hours a quite shocking attack on the leader by leading lights of organisations like Members First, Progress and so on", she said.
"I regard this as a battle for the future existence of the Labour party". This is high stakes. "What Jon Lansman has outlined is a plan with Len McCluskey, the leader of Unite, to take control of the Labour party".
In a joint statement issued on Monday afternoon, Corbyn and Watson said the shadow cabinet had "agreed on the need to strengthen party unity".
"We will deny a voice to no one", he said.
"We have a mass membership now and it wants its voice to be heard", she told Today.
"Len McClusky has to show responsibility, too", he added.
"And what we need to do next is a number of things to change the nature of the Labour party".
She accused the deputy Labour leader of being part of an "unprecedented pattern of interference" in the Unite leadership contest.
He also discusses an affiliation with the Unite union, the largest trade union in the United Kingdom and Ireland.
'It is not a question of anyone disaffiliating from the Labour Party and affiliating to Momentum instead'.
"I think this is so serious, I think it's vital that ordinary members of Unite are made aware of this plan, that they know what's going on inside their union and they take action to block it". "If you succeed you will destroy the Labour Party as an electoral force, so you have to be stopped", Watson told Lansman over Twitter.
'It's no threat to the position of the Labour Party and the strength of the Labour Party.
Maybe this is just the fanboy in me who's been waiting more than a decade for this movie talking, but. this is a flawless poster. Stephen King's The Dark Tower is the most ambitious and expansive story from one of the world's most celebrated authors.
The highest ranking woman on the list was L'Oreal cosmetics shareholder Liliane Bettencourt, who was 14th with $39.5 billion. Trump slipped 220 spots on the list to 544 with an estimated $3.5 billion, a decline of $1 billion from a year ago .
In the film, the attractive Belle is imprisoned in an enchanted castle by a fearsome Beast , who soon falls in love with her. Sung by Watson, the song narrates a new scene in which Belle learns of her childhood and what happened to her mother.
The Wolverines have won seven straight games, including the Big Ten Championship and Sunday's upset victory over No.2 Louisville . Despite the upsets finally transpiring in the Round of 32, there are still three of the four No. 1 seeds in the tournament left.
President Donald Trump walks to the White House after arriving on Marine One, Sunday, March 19, 2017, in Washington. USA intelligence officials have not publicly raised the possibility of contacts between the Clintons and Moscow.
Defenders: Seamus Coleman, Cyrus Christie, Richard Keogh, Alex Pearce, John O'Shea, Andy Boyle, John Egan, Stephen Ward. Ireland will be without six players for Friday night's key Group D clash with Wales in Dublin.
Some MPs believe Mrs May could announce an early election next week when she triggers Article 50, beginning the Brexit process. There are rumours that the United Kingdom could go to the polls sooner, sparking a flurry at betting shops.
Lynch, 30, last played in the National Football League during the 2015 season with the Seahawks and appeared in seven games. His Beast Mode apparel line has a store in the city and helped establish the Fam 1st Family Foundation in the Bay Area.
Those with that interpretation included reporters from Fox News, CNN, The Hill, The Washington Times , Cox Media Group, and more. In the wake of emails that were released by Wikileaks, DNC Chairwoman Debbie Wasserman Schultz resigned from her post.
Under pressure, the people criticise him, so I am delighted to have John, with all the huge amount of mistakes he has". Like all matches, we create more chances but this is our problem, our problem is we don't score goals. "I love him.
Drake brings the heat on 'More Life'
United Kingdom rapper Giggs, PARTYNEXTDOOR, Sampha and the long awaited Kanye feature were my personal favorites. They reminded us we are on this Earth for only a heartbeat; there is only loving and being loved.
Egypt's president to visit Washington in April
The bilateral relations between Egypt and the USA have warmed since Trump took office in January. The upcoming visit will be the first for Al-Sisi to the USA since he took office in 2014.
Intel Announces First Optane SSDs for Data Centers
That's a far cry from Intel's previous claims of a thousand-fold increase in performance, but the results are still impressive. Intel has stated earlier that these drives will be eight times faster than the ordinary SSDs that are available in the market.