He said he believed the Government had struck the right balance between the rights of same-sex couples and its constitutional obligations.
The legislation provides a package of rights, obligations and protections for same-sex couples who register as civil partners in the areas of property, maintenance, pension and succession rights.
Fine Gael Justice Spokesman Charlie Flanagan welcomed the introduction of the legislation and said it was testament to how far Irish society had come.
Labour Party TD Brendan Howlin also welcomed the legislation but said it did not go far enough.
Mr Howlin said it did not reflect true equality as it did not offer marriage, but he recognised that that would require constitutional change.
Gay rights groups criticise Bill
Earlier, The National Lesbian and Gay Federation rejected the Bill, and reiterated calls for the immediate introduction of a civil marriage option.
The Union of Students in Ireland says the proposed Bill will offer a number of legal rights to lesbian and gay couples but falls short of offering many of the rights and protections covered by civil marriage.
The USI says the Bill ‘refuses to recognise the existence of same sex families, leaving children of same sex couples vulnerable and unprotected under Irish law’.
USI Lesbian Gay Bi-sexual Transgender Rights Officer Laura Finlay said: ‘The implementation of this Civil Partnership Bill will only serve to enshrine in law the second class citizenship of LGBT people in this country.
‘It is wholly unfair and sends out the message that gay people in Ireland are not equal to their heterosexual counterparts.’
In the recent NLGF report, Burning Issues, lesbian, gay, bisexual and transgender people named equal marriage rights as their number one priority.
‘Burning Issues proved definitively that there is no appetite among the LGBT community for civil partnership. They recognise that not only will the bill deny them full rights, it will discriminate against them even further,’ said NLGF Chairperson Ailbhe Smyth.
She said, ‘Civil partnership will fuel such anti-gay sentiments by signalling: ‘Yes, you are different’. The Government must admit that provision of Civil Partnership as the only relationship recognition option for LGBT people is a serious mistake.’
Meanwhile, MarriagEquality has issued a letter to Taoiseach Brian Cowen urging him to intervene so that the proposed Civil Partnership legislation be upgraded to legislation that would give equal civil marriage rights to same-sex couples.
MarriagEquality argues that civil partnership as the only option for same-sex couples promotes inequality.
Bill heralds a new era for same-sex couples — Ahern
Civil partnership bill: What the new legislation will mean in practice
Mixed reaction to Civil Partnership Bill
Gay people push for full marriage rights
Gay rights campaigners hit out at civil partnership plans