LONDON, Sept 30 (Reuters) - Vodafone ( VOD ) and

Hutchison's Three UK will commit to low tariffs on

their value brand for two years and give better access to

wholesale operators, making new pledges to the regulator to try

to get approval for their $19 billion merger.

Britain's antitrust regulator, the Competition and

Markets Authority (CMA), is due to make its final decision on

the tie-up between the two mobile operators by Dec. 7.

The companies said they would maintain prices on the SMARTY

value brand at 10 pounds or below, as well as keep social

tariffs and exclude vulnerable customers from mid-contract price

rises, according to a submission to the CMA published on Monday.

They said they were also prepared to commit to offer access

to their joint network on pre-agreed terms to third-party

operators with 2.5 million or fewer customers.

The CMA said earlier this month that the deal, which reduces

the number of networks from four to three, could push up prices

for customers.

But they signalled it could received clearance if the

two parties could guarantee it would be positive for consumers,

network quality and wholesale competitors like Sky Mobile.

The merger will create a market leading competitor to

BT's EE and Virgin Media O2 .

Vodafone ( VOD ) and Three UK said they disagreed with CMA's

view on consumer pricing, and pointed to their existing promises

to invest 11 billion pounds in their joint network and sell some

of their combined spectrum to VMO2.

However, they also offered the new pledges as part of a

final push to get the deal cleared.

"We will continue to positively engage with them (the

CMA) to resolve outstanding matters," they said in a statement.