diff --git a/Cargo.toml b/Cargo.toml
index 413212bd..fe15f05e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -38,7 +38,7 @@ version = "0.1.39"
 default-features = false
 
 [dependencies.num-traits]
-version = "0.2.4"
+version = "0.2.7"
 default-features = false
 
 [dependencies.rand]
diff --git a/src/bigint.rs b/src/bigint.rs
index 4df63de6..3cfc5cfd 100644
--- a/src/bigint.rs
+++ b/src/bigint.rs
@@ -756,6 +756,12 @@ impl Zero for BigInt {
         BigInt::from_biguint(NoSign, Zero::zero())
     }
 
+    #[inline]
+    fn set_zero(&mut self) {
+        self.data.set_zero();
+        self.sign = NoSign;
+    }
+
     #[inline]
     fn is_zero(&self) -> bool {
         self.sign == NoSign
@@ -768,6 +774,12 @@ impl One for BigInt {
         BigInt::from_biguint(Plus, One::one())
     }
 
+    #[inline]
+    fn set_one(&mut self) {
+        self.data.set_one();
+        self.sign = Plus;
+    }
+
     #[inline]
     fn is_one(&self) -> bool {
         self.sign == Plus && self.data.is_one()
diff --git a/src/biguint.rs b/src/biguint.rs
index da953dac..f1306fef 100644
--- a/src/biguint.rs
+++ b/src/biguint.rs
@@ -417,6 +417,11 @@ impl Zero for BigUint {
         BigUint::new(Vec::new())
     }
 
+    #[inline]
+    fn set_zero(&mut self) {
+        self.data.clear();
+    }
+
     #[inline]
     fn is_zero(&self) -> bool {
         self.data.is_empty()
@@ -429,6 +434,12 @@ impl One for BigUint {
         BigUint::new(vec![1])
     }
 
+    #[inline]
+    fn set_one(&mut self) {
+        self.data.clear();
+        self.data.push(1);
+    }
+
     #[inline]
     fn is_one(&self) -> bool {
         self.data[..] == [1]