June 11 (Reuters) - U.S. private equity firm KKR

and Assura have agreed on the terms of a "best and

final" offer for the British healthcare real estate investor's

sale, valuing it at nearly 1.7 billion pounds ($2.29 billion),

the companies said on Wednesday.

The latest proposal from KKR and private equity firm

Stonepeak Partners of 52.1 pence a share including dividends

trumps the 51.7 pence offered by rival suitor Primary Health

Properties ( PHPRF )

last month

.

Assura joins a growing list of UK companies being bought

out and taken private by overseas private equity firms or

investment companies, attracted by cheap valuations.

($1 = 0.7415 pounds)