West Ham remain in talks with Swansea over deals to sign defender Alfie Mawson and goalkeeper Lukasz Fabianski, according to Sky sources.
Swansea have already rejected bids from West Ham for both players, but it is understood both parties are edging closer to an agreement over the respective fees.
Sky sources understand the negotiations between the clubs centre around the structure of the payments in both deals.
West Ham conceded the joint-most goals in the Premier League last season - 68 - and new manager Manuel Pellegrini is keen to strengthen his defensive options ahead of the new campaign.
Mawson, who attracted interest from West Ham in January, has two years remaining on his contract at the Liberty Stadium.
He made 44 appearances for Swansea last season, scoring three goals, but was unable to stop them from dropping out of the Premier League.
Fabianski, who has one year remaining on his contract, played in all of the Swans' 38 Premier League games last season and is in Poland's World Cup squad for this summer's tournament in Russia.