ultimately the employment agreement is signed between you and the employer. even if you take it to the last stage with the offer letter in hand, you are still entitled to walk away.

the recruiter can rush you all he/she wants but it is neither his/her call to hire you, nor inform the hirer that you don't want to proceed.

just tell the recruiter whatever it takes to get the written offer in hand, before deciding. as a poster above suggests, you can phrase it non-committally if you are afraid of being blacklisted by the recruiter.