Jan Vertonghen is expected to be offered a new contract by Tottenham before the end of the season as the club seek to secure the future of their most important assets.

The Belgium defender moved to White Hart Lane from Ajax in the summer of 2012 on a four-year deal, which is thought to include the option of a fifth year. Since moving to the Premier League in a £9.6million deal, including a contract worth about £40,000 per week, Vertonghen has been one of Spurs’ best players and has enhanced his reputation.

If Spurs were to sell Vertonghen they could command at least double what they paid for him. Yet the club are very keen to keep the 26-year-old, who is happy in north London, and are thought to be prepared to offer a deal in the region of £60,000 a week, which would move Vertonghen closer to Tottenham’s top earners.

Before Vertonghen joined Spurs, Barcelona, Arsenal and AC Milan all expressed a strong interest in him. Although Spurs are hardly likely to sell to their most bitter rivals, and Milan are having a very poor season, they may be vulnerable to an approach from Spain, especially if they fail to qualify for next season’s Champions League.

Tottenham aim to ward off any approaches by tying down Vertonghen for the long term. Despite an injury that ruled him out for nearly two months, Vertonghen came straight back into the team for the 1-1 draw at Hull on February 9 and produced a polished performance. He also started the 1-0 win over Everton two days ago and is expected to keep his place in the side for tomorrow night’s Premier League game at Newcastle.

Tottenham’s head coach, Tim Sherwood, has described Vertonghen as the best left-sided centre-back in the division and intends to use him primarily in his favourite position. Vertonghen is thought have become slightly disgruntled when Sherwood’s predecessor, Andre Villas-Boas, insisted on moving him to left-back when Danny Rose was injured.

Meanwhile, Sherwood hopes to have Emmanuel Adebayor available for the match at St James’ Park, even though the forward needed lengthy treatment in the dressing room after the Everton game. Adebayor played that game with a dead leg but still scored the winning goal, his seventh in 11 matches since Sherwood took charge.