Monk will lose two key players next month, with midfielder Ki Sung-yueng and top goalscorer Wilfried Bony away on international duty.
Ki will join South Korea in Australia for the Asian Cup, while Bony heads off to the Africa Cup of Nations with Ivory Coast.
With that in mind, Monk has set his sights on recruiting two new players as cover in the January transfer window.
Monk also wants another left-back to provide competition for Neil Taylor.
"There's stuff we're looking at in the transfer window, but it will come down to availability and affordability," said Monk.
"It has to be right for myself and the team and the club. Not that much work is required, but the squad needs strengthening.
"A striker on loan would be an OK option, but it's more a loan with a view to looking if he [could] do something in the future as well.
"Neil is the only recognised left-back at the club right now and in terms of that competition, he needs to be pushed and we need to have that.
"Ki going away could be a position that we need to look at too, but again it has to be the right type of player for us as we have other good players."
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