LONDON (Reuters) - Two senior members of British Prime Minister David Cameron's ruling Conservative party spoke out to calm growing talk of a leadership challenge against him on Friday, days before a closely watched budget.

Halfway through a five-year term, Cameron's Conservatives are trailing the opposition Labour party by 10 percent in the polls, the economy is stagnant, some lawmakers say they are unhappy with his leadership, and one of his ministers is being touted as a possible replacement.

But on Friday, two senior party figures insisted Cameron's leadership was not under threat ahead of a general election in 2015, dismissing media stories which have suggested others may be positioning themselves to usurp him.

"David Cameron is more popular than all of us ... more popular than all of the party in the country, which is a key point that lots of people do recognize," said Conservative Party Chairman Grant Shapps.

Talk of a leadership challenge was "for the birds and certainly not for today," he told political magazine The House.

London Mayor Boris Johnson, who has himself been tipped as a leadership candidate, agreed. "People need some sort of political drama so they're inventing one. I think it's complete nonsense," he told The Sun newspaper.

Cameron is going through a bruising time politically.

His party was beaten into third place in a vote for a parliamentary seat earlier this month, half of his party rebelled against him over a gay marriage law last month, he is at odds with his junior coalition partner on press regulation, and is being criticized for his ambiguous stance on an alcohol control law.

SPECULATION SWIRLS

Most analysts believe the malcontents are in the minority and would have scant chance of unseating Cameron if they chose to try. No serious rivals have emerged, they say, and even most internal detractors think Cameron should remain leader.

But, as his finance minister, George Osborne, prepares for a budget on Wednesday that will give the Conservatives a chance to tip the political scales in their favor, Cameron's position remains the subject of almost weekly speculation.

This week, Theresa May, the home secretary or interior minister, delivered a speech that went well beyond her brief, prompting media speculation she was angling for Cameron's job.

Labour taunted Cameron over the speech in parliament as Conservative party strategists told MPs to curb their criticism of Cameron on social media and to decide if they were commentators or participants in the battle to win the next election.

Johnson said it was time for the party to unite.

"If ministers are setting out their stall now, it strikes me as being very odd," he said. "They should save their breath and cool their porridge. Put a sock in it and get on and back the Prime Minister."

In a party political TV broadcast earlier this week, Cameron shrugged off the speculation about his leadership as "rubbish".

"It's so vital that you look to the horizon and not tomorrow's headlines, because there is a sort of daily battle of this story and that event," he said. "It's all rubbish."

Several Conservative lawmakers disenchanted with his leadership have said they would judge him by five "key tests".

In their eyes, he has already failed two of them after his party lost a vote for a parliamentary seat in the constituency of Eastleigh earlier this month and the country lost its top-notch AAA credit rating in February.

Three tests remain: setting out a successful budget on Wednesday, avoiding a triple-dip recession, and performing reasonably well in local elections in May.

(Editing by Robin Pomeroy)

Aviva shareholders will get 19 pence from 2012 earnings, compared with 26 pence the previous year, and well below the 25.6 pence forecast by analysts in a company poll, the insurer said on Thursday.

""This was a difficult decision, but it was absolutely necessary to give certainty to our shareholders, to reduce debt, and to put Aviva on a sound footing for the future," Aviva Chief Executive Mark Wilson told reporters, adding that he and other top executives would get no bonuses or pay rises this year.

The dividend cut, Aviva's second in four years, came as the company reported a 15 percent drop in operating profit to 2.13 billion pounds, broadly in line with forecasts.

Standard Lifesaid it would pay investors a special dividend of 302 million pounds, on top of a 6.5 percent increase in the regular payout, after forecast-beating profit growth last year contributed to a "very strong" capital position.

Shares in Aviva were down 13 percent by 1050 GMT, the steepest faller in the FTSE 100share index.

That wiped 1.3 billion pounds ($1.96 billion) off the company's value, relegating it to fourth position from second in the ranking of British insurers by market capitalization, behind Old Mutualand Legal & General . Old Mutual and Legal & General both announced divided hikes for 2012.

"Aviva has the worst dividend paying record of all the major UK life companies, and it will clearly take some considerable time to persuade investors that the latest management team have got it right," said Investec analyst Kevin Ryan.

The dividend cut is the latest step in a reorganization launched by Aviva last July after investors irked by a persistently weak share price forced out Wilson's predecessor, Andrew Moss.

Under the plan, the insurer has cut costs and raised about 2.4 billion pounds by selling less profitable businesses that tie up too much capital, including its subsidiary in the United States.

That helped double Aviva's capital surplus to 7.1 billion pounds by the end of 2012, addressing investor concerns that the insurer did not have strong enough cash reserves given its heavy exposure to the troubled euro zone, Wilson said.

But the disposals also boosted Aviva's debt as a proportion of assets, putting it under pressure to repay what it owes more quickly.

Wilson, formerly head of Asian insurer AIA , said Aviva now aimed to generate more cash from its flagship British and Canadian businesses while investing in units with good growth potential, including its Polish, Turkish and Asian arms.

"The insurance sector has made an industry out of complexity," he said.

"We need to be simple, we need to be understandable, we need to be as dependable as a Swiss clock, and that is my promise."

One of the European insurance sector's main attractions for stock market investors is its ability to pay relatively big dividends, reflecting its predictable revenues as customers renew their policies annually.

Standard Life announced a 2012 operating profit of 900 million pounds, up 65 percent, exceeding the 400 to 600 million target set out in its directors' long-term incentive plan, and entitling them to the maximum payout under the scheme, Chief Executive David Nish said.

($1 = 0.6643 British pounds)

(Reporting by Myles Neligan; Editing by David Cowell and Susan Fenton)