diff --git a/src/PAST/NQP.pir b/src/PAST/NQP.pir
index 208a8e1376..32f1c094ea 100644
--- a/src/PAST/NQP.pir
+++ b/src/PAST/NQP.pir
@@ -453,6 +453,7 @@ entry to produce the node to be returned.
     maphash['div_n']    = 'div__Nnn'
     maphash['mod_i']    = 'mod__Iii'
     maphash['mod_I']    = 'nqp_bigint_mod__PPPP'
+    maphash['expmod_I'] = 'nqp_bigint_exp_mod__PPPPP'
     maphash['mod_n']    = 'mod__Nnn'
     maphash['pow_n']    = 'pow__Nnn'
     maphash['pow_I']    = 'nqp_bigint_pow__PPPPP'
diff --git a/src/ops/nqp_bigint.ops b/src/ops/nqp_bigint.ops
index 6596cc42da..c8e4b5431b 100644
--- a/src/ops/nqp_bigint.ops
+++ b/src/ops/nqp_bigint.ops
@@ -176,6 +176,16 @@ inline op nqp_bigint_mod(out PMC, in PMC, in PMC, in PMC) :base_core {
     mp_mod(a, b, get_bigint(interp, $1));
 }
 
+inline op nqp_bigint_exp_mod(out PMC, in PMC, in PMC, in PMC, in PMC) :base_core {
+    mp_int *a = get_bigint(interp, $2);
+    mp_int *b = get_bigint(interp, $3);
+    mp_int *c = get_bigint(interp, $4);
+    $1 = REPR($5)->allocate(interp, STABLE($5));
+    REPR($1)->initialize(interp, STABLE($1), OBJECT_BODY($1));
+    mp_exptmod(a, b, c, get_bigint(interp, $1));
+}
+
+
 inline op nqp_bigint_neg(out PMC, in PMC, in PMC) :base_core {
     mp_int *a = get_bigint(interp, $2);
     $1 = REPR($3)->allocate(interp, STABLE($3));
diff --git a/t/nqp/60-bigint.t b/t/nqp/60-bigint.t
index ed6763d3a0..9e08aa2de8 100644
--- a/t/nqp/60-bigint.t
+++ b/t/nqp/60-bigint.t
@@ -1,7 +1,7 @@
 #! nqp
 use nqpmo;
 
-plan(30);
+plan(31);
 
 my $knowhow := pir::get_knowhow__P();
 my $bi_type := $knowhow.new_type(:name('TestBigInt'), :repr('P6bigint'));
@@ -84,3 +84,10 @@ ok(nqp::iseq_n($float, nqp::tonum_I(nqp::fromnum_I($float, $bi_type))),
 
 ok(nqp::base_I(box(-1234), 10) eq '-1234', 'base_I with base 10');
 ok(nqp::base_I(box(-1234), 16) eq '-4D2',  'base_I with base 16');
+
+ok(str(nqp::expmod_I(
+    nqp::fromstr_I('2988348162058574136915891421498819466320163312926952423791023078876139', $bi_type),
+    nqp::fromstr_I('2351399303373464486466122544523690094744975233415544072992656881240319', $bi_type),
+    nqp::fromstr_I('10000000000000000000000000000000000000000', $bi_type),
+    $bi_type,
+)) eq '1527229998585248450016808958343740453059', 'nqp::expmod_I');