* Deal could be closed between July 1 and July 13-Sonntag
* SNB and FINMA putting pressure on UBS to settle-Sonntag
* NZZ am Sonntag says U.S. has names of 10,000 UBS clients
(Adds details from NZZ am Sonntag report)
ZURICH, June 28 (Reuters) - Switzerland's UBS is to pay 3 to 5 billion Swiss francs ($2.77-$4.62 billion) in the next two weeks to settle a U.S. tax probe into the bank, Swiss newspaper Sonntag reported on Sunday.
The U.S. government is suing UBS to get the names of 52,000 Americans who allegedly hid nearly $15 billion in assets from the taxman.
Sonntag, which said the figure of 3 to 5 billion francs had been confirmed by three independent sources, reported a deal could be signed between July 1 and July 13.
UBS said late on Thursday it plans to raise $3.5 billion of new capital -- a move welcomed by Swiss banking regulator FINMA as it strengthens UBS' capital base.
Separately, Switzerland's NZZ am Sonntag reported a deal between the U.S. authorities and UBS could be close as U.S. lawyers said the Internal Revenue Service (IRS) already had the names of more than 10,000 UBS clients.
It was, however, unclear if a deal would be reached before July 13, NZZ am Sonntag said.
UBS, the world's largest wealth manager, which has seen big client outflows over the U.S. case, declined to comment on the Sonntag and NZZ am Sonntag reports.
Earlier this week, the U.S. Justice Department said it was still willing to consider a settlement, but denied it was planning to drop the case and said it would file a brief seeking an enforcement of the summons on June 30.
A U.S. filing on the matter is due on June 30 and a hearing before a judge in Miami is set for July 13.
Several attorneys and others following the case are sceptical the United States would drop the case without major Swiss concessions, given the momentum against tax havens and coming deadlines for taxpayers to come forward voluntarily.
Sonntag reported UBS was under pressure from the Swiss National Bank and FINMA to sign a deal as they look to bring stability back to the Swiss banking industry which is battling with the global crisis and a crackdown on banking secrecy.
Earlier this year, UBS agreed to give a small number of client names and pay a fine of $780 million to end U.S. criminal fraud charges that it assisted rich Americans to evade taxes.
Switzerland and the United States announced last week they had reached agreement on a double taxation treaty.
Some analysts have said this made a deal in the UBS case more likely, although the United States was unlikely to settle early to keep the pressure on UBS clients to declare themselves voluntarily. ($1=1.083 Swiss Franc) (Reporting by Katie Reid; Editing by Jon Loades-Carter)