Euan Murray won his first Scotland cap against Romania in 2005

Prop Murray, who has seven caps, will join Northampton next season on a two-year deal.

Six-times capped wing Lamont, younger brother of Sean, is in talks with English clubs, one of which is Sale.

Glasgow hooker Scott Lawson has already signed a deal with the Sharks, one of six others to quit Scottish clubs.

Edinburgh have lost back-row Simon Taylor to Stade Francais and centre Rob Dewey to Ulster, while flanker Al Strokosch and prop Ally Dickinson have both signed for Gloucester.

Ulster have also signed wing Simon Danielli from the Borders.

"I'm looking forward to coming to Northampton next season," said 26-year-old Murray, who is yet to undergo a medical.

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"The facilities and squad are world class and I'm looking forward to helping them get back to the top of the game in England.

"Obviously having Tom Smith at the Saints made the decision easier. He's a legend in the game; a British Lion as well as a Scotsman so it'll be fantastic to play with him."

In a statement, the SRU said it was powerless to prevent players accepting more lucrative offers elsewhere.

"Whilst recognising it is inevitable there will always be player movement at this stage in any season, particularly in a World Cup year, Scottish Rugby also accepts that it finds it hard and sometimes impossible to compete against larger, more financially secure clubs in other northern hemisphere countries," it said.

"Scottish Rugby has endeavoured to make the most of its limited finances and facilities in today's professional game.

"However, despite many efforts to keep its talented players in Scotland, market forces dictate this is not a situation the governing body has sufficient powers to control."